Handicapping the Veepstakes: The Case For (and Against) Marco Rubio Alan Diaz / AP Sen. Marco Rubio of Florida speaks in Miami, Jan. 27, 2012. Having fended off his rivals to capture the Republican presidential nomination, Mitt Romney now faces one of the critical moments of his candidacy: the selection of a running mate. Once a bureaucratic backwater, the role of the vice president has expanded in recent years, and the vetting process has morphed accordingly. To oversee the tricky task of tapping a VP, Romney has enlisted his senior adviser Beth Myers, a longtime confidante who served as his chief of staff in the Massachusetts statehouse and helmed his 2008 presidential run. Like her boss, Myers is described by those who know her as meticulous and competent, which should soothe the fears of a party still smarting from the haphazard vetting that yielded Sarah Palin in 2008. Romney and his advisers have been characteristically tight-lipped about the process, but one thing is clear. "He will be the opposite of John McCain, who made a seat-of-the-pants decision with Palin," says Larry Sabato, a political analyst at the University of Virginia. That does not necessarily mean the cautious candidate will make a cautious pick. It may be a bad decision. It may be a good decision. But it will be a well thought-out pick. Whether that leads to a safe choice or a wild-card choice is anybody's guess. MORE: Why Marco Rubio's Vice-Presidential Stock Is Overvalued Let the guessing begin. Here's the first in a series of snapshots (delivered in no particular order) of people likely to be on Romney's short list: The Candidate: Marco Rubio, U.S. Senator from Florida The bio: Rubio's rise has been heralded as an American Dream. Born in Miami to Cuban parents, he was reared working-class, earned a law degree and entered the Florida House of Representatives by the time he was 30. He rose through the ranks in Tallahassee to become speaker, winning a reputation as a movement conservative in the process. In 2010, his Tea-Party backed insurgent campaign routed Charlie Crist in the Florida Senate primary. By the time he stepped into the upper chamber in Washington, Rubio had been anointed one of the brightest stars in the GOP constellation, and his carefully calibrated work since then has mostly reinforced that narrative. The case for: One of the axioms of presidential politics is you pick a running mate who shores up your weaknesses or provides an entree with critical coalitions. From a pragmatic standpoint, Rubio would help in more discrete ways than any other candidate. He is a favorite of Tea Partyers and movement conservatives, many of whom harbor lingering doubts about Romney's ideological credentials. A buzzy, boldface name, he seems likely to energize the factions of the base who remain cool to the former Massachusetts governor. Plenty of influential party elders, including Jeb Bush and Mike Huckabee, have suggested Romney look to the youthful, telegenic Rubio to fill out the ticket. Rubio also seems to check off a key demographic box. He's Hispanic, with the potential - on paper - to boost the GOP's standing with the fastest-growing demographic group in the country. Latinos could be the key to the White House in 2012, but the GOP's immigration policies have cost the party in the polls: in a recent survey by the Spanish-language network Univision, 72% of Hispanics said they didn't feel welcomed by the party. Finally, Rubio hails from a crucial swing state that is a linchpin of the Republican Party's Electoral College strategy. MORE: Exclusive Interview: Marco Rubio Challenges His Own Party on Latino Outreach The upside combination, and the fact that he's been floated as a candidate for so long, is why Rubio tops InTrade's prediction market with a 22% chance of selection. On multiple occasions, Romney has invoked Rubio as a star he admires. "I think he's one of the terrific leaders in our party," he told ABC's Diane Sawyer on Monday night, though he added, "I think it's way too early to begin narrowing down who the potential vice presidential nominees might be." The case against: At 40, the first-term Senator may be perceived as too inexperienced in a cycle marked by memories of the Palin debacle. Many Republican strategists say the paramount quality Romney is seeking in a running mate is the ability - and, perhaps as importantly, the popular perception of that ability - to step into the top job on Day One if needed. Rubio has an impressive but brief track record in Washington, and hasn't yet been fully vetted on the national stage. An outspoken proponent of fiscal discipline, he has faced questions about his own finances. A Washington Post reporter, whose biography of Rubio will compete this summer with the Senator's own account, suggested that Rubio had embellished his stirring personal story by saying his parents emigrated to the U.S to flee Castro's rule; in fact, they came to the country more than two years before the Cuban dictator came to power. Rubio told the Post the error was inadvertent and he was simply repeating family lore. Neither of these tidbits has inflicted much damage. But a senior adviser to a rival presidential campaign says he believes Romney's camp may be deterred by a more innocuous revelation: that Rubio, a practicing Roman Catholic, was baptized into the Mormon church as a young child. Holding this against Rubio would seem remarkably unfair. But among Evangelicals, some of whom remain skittish about Romney's Mormon faith, the affiliation could be "very damaging" to Romney, says the rival adviser. Having a Mormon on the top of the ticket and a former Mormon on the bottom of the ticket would be courting disaster with Evangelicals. It's just too bizarre. There is another argument against Rubio's selection that has nothing to do with psychology or religious suspicions: the demographic advantages he appears to carry may be a mirage. Rubio's presence on the ticket might not help deliver Hispanics or move the needle in the Sunshine State. A PPP poll released Tuesday found that adding Rubio to the ticket actually knocked Romney down two points in Florida. "All Rubio does for Romney is give him the opportunity to make the case to Hispanics," Sabato says. That may be a tough sell in light of the hardline stance Romney has adopted on immigration during the primary, not least because the historic divisions between Cubans and other Latinos may muddy Rubio's own appeal with such groups outside Florida. Finally, there is the question of whether Rubio wants the job. He was not one of Romney's early endorsers, and since coming aboard, his support for the former Massachusetts governor has been tepid. "There are a lot of other people out there that some of us wish had run for President - but they didn't," he said. I think Mitt Romney would be a fine president, and he'd be way better than the guy who's there right now. Moreover, he has repeatedly insisted, in fairly Shermanesque fashion, that he wouldn't take the gig even if asked. Pressed by the New Yorker's Ken Auletta, Rubio said last month: "I'm not going to be the Vice-Presidential nominee. If I say I'm not going to be it, obviously I'm not going to accept it. I'm focused on this job. And I've said that a hundred times, I don't know how many more - I mean, it's almost to the point now where I don't know how else to say it. VIDEO: Marco Rubio's Tea Party Triumph