Handicapping a potential veep shortlist By NBC's Mark Murray and Domenico Montanaro Go big or go boring? That's the question for Mitt Romney and his campaign team as they consider a vice-presidential running mate to join the GOP presidential ticket. The cliche first rule in picking a No.2 is, "First, do no harm." And that's the lesson the Romney campaign likely learned from John McCain's 2008 pick of Sarah Palin. The conventional wisdom because of it? Romney makes a "safe" pick in 2012. Then again, GOP presidential nominees have had a history of making surprises - George H.W. Bush's selection of Dan Quayle, George W. Bush choosing Dick Cheney, and McCain picking Palin. Vote now: Who would be the strongest pick for Romney? Here is the NBC Political Unit's guide to Mitt Romney's veep pool - a look at nine of the most-frequently mentioned candidates potentially vying for the job. Ted Aljibe / AFP/Getty Images Sen. Kelly Ayotte speaks during a press conference at the U.S. embassy in Manila on Jan. 17, 2012, while fellow senator John McCain listens. Kelly Ayotte, New Hampshire senator Age: 44 Education: B.A., Pennsylvania State University, 1990; J.D., Villanova, 1993 Elected Office: New Hampshire attorney general, 2004-2009; U.S. senator, 2011-present Professional Career: Attorney Religion: Catholic Marital Status: Married to Joe Daley Children: Katherine and Jacob Strengths: Ayotte is the sole female in Romney's pool of top-tier veep possibilities, and could potentially help him erase the gender gap he faces against incumbent President Barack Obama. The latest NBC News /WSJ poll found Obama leading Romney among women by 13 points, 52 percent to 39 percent. She's young, telegenic, and conservative. An early backer of Romney (she endorsed him in Nov. 2011), Ayotte has regularly campaigned for, and with, the former Massachusetts governor. Her most recent campaign appearance with Romney took place on July 4 in Wolfeboro, N.H. She hails from a key battleground state that Obama won by nearly 10 points in 2008. That said, a recent NBC-Marist poll shows that adding Ayotte to the GOP ticket doesn't really increase Romney's poll standing in the Granite State. Weaknesses: Ayotte has been a U.S. senator for less than two years, which - fair or not - could draw comparisons to Sarah Palin, a conservative, female politician who served in major statewide office for less than two years before joining a GOP presidential ticket. If former Massachusetts Gov. Mitt Romney selected Ayotte (from neighboring New Hampshire), he wouldn't gain much geographical diversity. Then again, a ticket consisting of southerners Bill Clinton (from Arkansas) and Al Gore (from Tennessee) won the White House - twice. Jason Redmond / Reuters New Jersey Gov. Chris Christie speaks at the Ronald Reagan Presidential Library and Museum in Simi Valley, Calif., on Sept. Chris Christie, New Jersey governor Age: 49 Education: B.A., University of Delaware, 1984; J.D., Seton Hall, 1987 Elected Office: Member of the Morris County Board of Chosen Freeholders, 1997; New Jersey governor, 2010-present Professional Career: Lawyer; attorney for the District of New Jersey, 2002-2008 Religion: Catholic Marital Status: Married to Mary Pat Foster Children: Andrew, Sarah, Patrick, and Bridget He is the "bold" pick - a firebrand, who doesn't shirk from battle. That demeanor fires up the GOP base, which loves a fight and wants someone to take it to Obama. He balances out Romney's somewhat careful, somewhat bland demeanor. He's seen as a problem solver - someone willing to deliver tough medicine, especially to public workers, in order to balance a budget. That would appeal to those who believe debt and deficits are top issues in 2012. Pushed to diversify N.J."s state Supreme Court, he nominated an openly gay African-American and a Korean-born prosecutor. Both were blocked by Democrats. This could help deflate the perception of a Republican party largely in favor of white men at the helm. Though Christie's moderate policy views (on things like gun control and immigration) might appeal to independents, his demeanor might not - he's brashly gone after public workers, a sector that's struggling. The most obvious thing about Christie is his weight. There would be legitimate health issues raised about his readiness to be president and the rigors that come with the job. Romney is looking for someone whose main objective isn't their own career - he needs someone soley devoted to getting him elected. Christie, with his larger-than-life personality, could overshadow Romney. The New York Times suggested that Christie's late arrival to Romney fundraiser might have created a negative impression with the presumptive nominee's team. His stance on gay marriage - vowing to veto it and then calling for a voter referendum - might hurt him with independents. Support for gay marriage has increasingly grown more popular. After he canceled the largest infrastructure project in the country (a new train tunnel across the Hudson River), a congressional investigation found he "exaggerated when he declared that unforeseen costs to the state were forcing him to cancel" it, The New York Times reported. Gov. Bobby Jindal of Louisiana addresses the Conservative Political Action Conference in Washington on Feb. 11, 2012. Bobby Jindal, Louisiana governor Age: 41 Education: B.A. 1991, Brown University; M. Lit, 1994, New College at the University of Oxford Elected Office: Governor, 2007-present; U.S. representative, 2004-2007 Professional Career: Health and Human Services assistant secretary, 2001-2003; president of the University of Louisiana Health System, 1999-2001; executive director of the National Bipartisan Commission on the Future of Medicine, 1998-1999; Secretary of the Louisiana Department of Health and Hospitals, 1996-1998 Religion: Catholic Marital Status: Married to Supriya Jolly Children: Selia Elizabeth, Shaun Robert, and Slade Ryan Jindal checks many boxes - he's conservative, a two-term governor, smart (he was a Rhodes Scholar at Oxford), and policy whiz (in his 20s, he helped overhaul Louisiana's public health system). As conservative writer Philip Klein put it, "He's more exciting than Portman and more experienced than Rubio." Despite that experience, Jindal - at age 41 - is still a young rising star in the Republican Party. And as an Indian-American, Jindal would bring diversity to the GOP presidential ticket. Unlike some other potential VP picks (like Ayotte, Pawlenty, and Portman) Jindal endorsed Rick Perry - a fellow governor from the South - during the GOP primaries. Jindal's first performance on the national stage - giving the Republican response to President Obama's first address to Congress - fell flat. His surprising aw-shucks, Howdy-Doody delivery was widely panned, even likened to Kenneth from NBC's "30 Rock." In March 2011, The New York Times reported that some corporations seeking business with Louisiana's state government (like AT&T, Marathon Oil, and Northup Grumman) donated a significant amount of money to the Supriya Jindal Foundation for Louisiana's Children, a charity established by Jindal's wife. This revelation came out after Jindal worked to tighten Louisiana's ethic rules and lessen the influence of special interests. Despite his insistence to construct sand berms to contain the BP oil spill - and his sharp criticism of the Obama administration during environmental disaster - a presidential commission concluded that Jindal "wasted $220 million building controversial sand berms that captured a "minuscule amount" of oil and proved to be "underwhelmingly effective" and "overwhelmingly expensive,"" USA Today reported. In 2004, Jindal wrote about witnessing an "exorcism" that he claimed cured a friend of cancer. Brendan Smialowski / Getty Images Gov. Bob McDonnell speaks during the 7th annual National Catholic Prayer Breakfast on April 27, 2011 in Washington. Bob McDonnell, Virginia governor Age: 58 Education: B.B.A., University of Notre Dame, 1976; M.B.A., Boston University, 1980; M.A./J.D. Regent University, 1989 Elected Office: House of Delegates, 1992-2006; Virginia attorney general, 2006-2009; governor 2010-present Professional Career: Lieutenant colonel in the U.S. Army (active, 1976-1981; reserve, 1981-1997) Religion: Catholic Marital Status: Married to Maureen Patricia Gardner Children: Jeanine, Cailin, Rachel, and twin boys - Robert and Sean Popular governor of a key swing state. His approval rating, according to a June Quinnipiac poll, was at 53 percent, though that's down from ratings in the high 50s and even 60s earlier in his term. He fits the image - good looks and an attractive family - including a daughter who fought in Iraq. McDonnell's not gaffe-prone. He rarely makes unforced errors. The governor is seen as smart, capable, and not overtly ideological - even though he's very conservative. Polls have shown a McDonnell pick wouldn't make much difference in Virginia, and Obama has continued to lead narrowly there. He got carried into the national fight about women's health rights when conservatives in Virginia proposed legislation to require invasive, trans-vaginal ultrasounds before women could undergo abortions. McDonnell ended up signing a watered-down version of the bill that required abdominal ultrasounds - but his approval rating among female voters still suffered because of it. He won big in his 2009 gubernatorial election, but the thesis that he wrote as a 34-year-old graduate student at an evangelical school in Virginia, might get fresh attention. He called feminists "detrimental" to the family and was critical of a 1965 Supreme Court decision that overturned a Connecticut law prohibiting married couples from using birth control. Todd Mcinturf / AP Former Minnesota Governor Tim Pawlenty addresses the 2012 Michigan Republican State Convention at Cobo Center in Detroit on May 19, 2012. Tim Pawlenty, former Minnesota governor Age: 51 Education: B.A., University of Minnesota, 1983; J.D., University of Minnesota, 1986 Elected Office: Eagan City Council, 1989; Minnesota House of Representatives, 1993-2003 (House majority leader from 1999-2003); governor of Minnesota, 2003-2011 Religion: Baptist/ Evangelical Marital Status: Married to Mary Anderson Children: Anna and Mara Although once a rival for the GOP presidential nomination, Pawlenty has become a constant and loyal surrogate for the Romney campaign. The two men campaigned together in Iowa before the caucuses there; Pawlenty stumped for the Romney campaign in Oklahoma in May; he shadowed Obama on his July bus tour; and even made a cameo in this Romney TV ad. His conservative credentials are rock-solid, which would please the GOP base. He opposes abortion (except in the cases of rape, incest, or when the mother's life is at stake), he and his wife are evangelical Christians, and he opposes same-sex marriage. As someone who has run for president before, Pawlenty is more than familiar with national scrutiny and high-profile debates. Could he put Minnesota in play for 2012? On the one hand, he's a former two-term governor of the state. On the other hand, he didn't receive 50 percent or more of the vote in those two races. In 2006, he barely won re-election against Democratic challenger Mike Hatch, 47percent to 46 percent, and he might have lost if his challenger hadn't referred to a female reporter as a "Republican whore." In 2008, by comparison, Obama won Minnesota, 54 percent to 44 percent. There are some holes in his conservative record. For starters, he signed a 75-cent fee on cigarettes, which some believe violated his "no new taxes" pledge. In addition, from late 2006 through 2008, Pawlenty championed policies to reduce greenhouse gases - like clean energy initiatives and cap and trade programs. In fact, he made climate change a signature issue as head of the National Governors Association. But during his presidential bid, he said this was a mistake. I look the American people in the eye and say I made a mistake. How much do conservatives really like Pawlenty? Remember that despite going all-in, he finished a disappointing third to Michele Bachmann and Ron Paul in the 2011 Ames Straw Poll. The day after that third-place finish, Pawlenty dropped out of the presidential race. Given that the economy is Issue No. 1 in this general election, observers criticized the economic plan that Pawlenty unveiled during his presidential bid. That plan cut taxes (top rate reduced to 25 percent) but balanced the budget by assuming a bullish 5 percent annual GDP growth. One critic called that growth assumption "patently ridiculous," according to The Associated Press. How much does Pawlenty owe Romney? According to an analysis by USA Today, more than half of the political donations Pawlenty received after he suspended his campaign - to pay down his debt - came from Romney donors. Romney loyalists, including 11 members of his family, several key fundraisers, his campaign aides and employees of the private-equity firm he helped create, donated more than $330,000 to Pawlenty since Aug. 14. In April, Pawlenty announced his campaign was debt free. Pawlenty recently joined the board of Smart Sand, a Pennsylvania firm that has built a large frac sand plant in Wisconsin. That sand is used in a controversial process to extract natural gas from rock. Sen. Rob Portman attends the 2012 Fiscal Summit on May 15, 2012 in Washington. Rob Portman, Ohio senator Age: 56 Education: B.A., Dartmouth College, 1979; J.D., University of Michigan Law School, 1984 Elected Office: U.S. representative, 1993-2005; U.S. senator 2011-present Professional Career: Attorney; business owner; U.S. trade representative, 2005-2006; director of the Office of Management and Budget, 2006-2007 Religion: Methodist Marital Status: Married to Jane Portman Children: Jed, Will, and Sally Portman hails from the battleground of Ohio, which could very well decide the election. He won 59 percent of the vote in his 2010 Senate campaign in the state. If you're looking for the exact opposite of Palin, it might be Portman - a former congressman, OMB director, and U.S. trade representative. He's also been the go-to guy for GOP mock debate preparation, having played Obama (in 2008), John Edwards (in 2004), Hillary Clinton (in 2000), and Joe Lieberman (in 2000). With the number of conservatives urging a "boring" pick, Portman certainly fits that bill - in the most positive sense of the word. He wouldn't make mistakes and would start out as inoffensive to independents. He's not a firebrand; he's generally seen as polite and sober - which could also appeal to independents. Romney currently has no direct ties to the Bush legacy. But Portman could take that away - he not only worked for the George W. Bush administration, but he owes much of his career to that political family. As Bush's OMB director (from 2006-2007), Portman presided over a period of time when the federal government was running deficits. That deficit would climb even higher after the housing bubble burst and the financial industry nose-dived in 2008. He's not even two years into his first term as senator. While "boring" has an upside, it also has a downside, too. A potential Romney-Portman ticket has been dubbed "boredom squared." Brian Blanco / EPA Sen. Marco Rubio addresses attendees at the NALEO conference in Orlando, Fla., on June 22, 2012. Marco Rubio, Florida senator Age: 41 Education: B.A., University of Florida, 1993; J.D. University of Miami, 1996 Elected Office: Florida House of Representatives, 2000-2008 (elected Speaker of the Florida State House, 2006-2008); U.S. senator, 2011-present Professional Career: City Commissioner for West Miami Religion: Catholic Marital Status: Married to Jeanette Dousdebes Children: Amanda, Daniela, Anthony, and Dominic The GOP's conservative base views Rubio as a rock star, so he could help Romney with a right-flank that's often had its suspicions about the former Massachusetts governor. As a Latino, he could potentially help with this fast-growing demographic group - and he'd make history as the first Latino to be on a major political party's presidential ticket. However, there's a question whether Mexican-Americans and Latinos with roots in Central America would identify with a Cuban-American. At age 41, he'd give the Romney ticket a jolt of youthful energy. As a senator from Florida, Rubio could help Romney in this must-win battleground state for the GOP. But polling suggests that adding Rubio to the ticket doesn't boost Romney's poll standing in the Sunshine State. Given his less than two years in the U.S. Senate, Rubio as the VP nominee would raise questions if he's prepared enough to serve a heartbeat away from the presidency - and it would (fairly or not) draw comparisons to Sarah Palin. Obama, by comparison, spent four years in the U.S. Senate before becoming president. The revelation, in 2011, that Rubio's parents originally migrated to United States before Fidel Castro came to power - despite his impression and statements to the contrary - highlights the lack of vetting he's received on the national stage. The additional revelation that Rubio was baptized as a Mormon (though he's now Catholic) could bring more attention to Romney's faith. And he's not exactly a model for fiscal responsibility: Rubio charged more than $100,000 to state GOP credit cards, had racked up nearly $1 million in debt, and had nearly foreclosed on a home. What's more, his friendship with the scandal-plagued David Rivera could be problematic as well. Larry Downing / Reuters Rep. Paul Ryan listens during a campaign event at Monterey Mills in Janesville, Wis., on June 18, 2012. Paul Ryan, Wisconsin congressman Age: 42 Education: B.A., Miami University in Oxford, Ohio, 1992 Elected Office: U.S. representative, 1999-present Professional Career: Marketing consultant, congressional aide Religion: Catholic Marital Status: Married to Janna Ryan Children: Elizabeth, Charles, and Samuel As chairman of the House Budget Committee, the 42-year-old Ryan is a young rising star in the GOP, and has become their chief spokesman when it comes to reducing the deficit and debt. Romney picking Ryan as his running mate would signal that he's doubling down on an austerity/deficit-reduction message. Indeed, while the Obama campaign and Democrats could point to visible improvements with the economy over the past three years (a lower unemployment rate, stronger GDP growth), there hasn't been much progress in reducing the deficit. The deficit was $1.4 trillion in FY "09; $1.3 trillion in "10; $1.5 trillion in "11 (projected); and $1.1 billion in "12 (projected). Ryan hails from a battleground state - Wisconsin - where polls show Romney currently trailing Obama. Obama actually won Ryan's district in 2008, 51 percent to 47 percent. Comfort level: When Romney campaigned with Ryan in the lead-up to the April 3 Wisconsin primary, the two men demonstrated a rapport not seen with other surrogates. He would be a person to please both the conservative intelligentsia and the Tea Party base. Ryan's budget plan has become a lightning rod, and it will be a focus of Democratic attacks in the fall. The most controversial component of the plan is that it significantly transforms Medicare, which is regarded as the government's most popular program. There are also holes in Ryan's budget-hawk armor: He voted for some of the biggest drivers of the deficit/debt: the Bush tax cuts, the Iraq war, and the Medicare prescription-drug benefit. Moreover, Ryan voted against the recommendations of the bipartisan Simpson-Bowles commission. A member of Congress, Ryan has never held statewide office. He also has no foreign-policy experience. Both could be liabilities. Bill Clark / Roll Call via Getty Images Sen. John Thune speaks to reporters after the Senate Republicans' policy lunch in the Capitol on Dec. 13, 2011. John Thune, South Dakota senator Age: 51 Elected Office: U.S. senator, 2005-present; U.S. representative, 1996-2002 Professional Career: Executive director of the South Dakota Municipal League, 1993-1996; South Dakota Railroad director, 199-1993;executive director of the South Dakota Republican Party, 1989-1991; special assistant to the U.S. Small Business Administration, 1987-1989; legislative assistant to U.S. Sen. James Abdnor, 1985-1987 Education: B.A., Biola University, 1983; M.B.A., University of South Dakota, 1984 Religion: Baptist Marital Status: Married to Kimberley Weems Children: Larissa, Brittany Like Romney, he looks the part - Thune is both handsome and telegenic. He could help with evangelicals, and is revered in conservative circles for defeating then-Democratic Senate Majority Leader Tom Daschle. Thune is an early Romney endorser. He made the endorsement in Iowa, which borders South Dakota, in hopes of helping Romney in the caucuses. He brings no geographical advantage to the ticket. South Dakota is solid Republican (although, as mentioned above, it borders Iowa). He's a former lobbyist, and that past work could play directly into Obama attacks. He also voted for TARP in 2008, which wouldn't please the conservative/Tea Party base. If Thune were on the ticket, that might contradict the GOP's fiscal debt/deficit message. Was named "Porker of the Month" by a watchdog group in Nov. 2006. NBC's Adam Ruiz-Perez and Steven Lovern contributed to this report.