A Political Tipsheet for the Rest of Us Friday, Jan. 6, 2012 PILING ON ROMNEY: With days to go before New Hampshire's primary, rivals for the Republican presidential nomination are hammering away at leader-of-the-pack Mitt Romney, contending he lacks of a core set of beliefs. They're hoping to exploit one of Romney's biggest vulnerabilities - his shifts on issues that have led to charges of political opportunism - while pushing character issues to the forefront of a contest that has been dominated by the economy. For now, the former Massachusetts governor appears set to win New Hampshire, with his rivals now eyeing South Carolina to slow his momentum. PILING ON SANTORUM: Former Pennsylvania Sen. Rick Santorum is drawing heat from rivals for his votes to extend the debt ceiling and for pet projects for his state. Both Texas Rep. Ron Paul, who finished behind Santorum in Iowa, and his son, Sen. Rand Paul of Kentucky, criticized Santorum for voting several times to raise the debt ceiling and fund the Education Department, one of the Cabinet-level agencies Paul would cut. Sen. John McCain, campaigning with Mitt Romney in South Carolina, criticized Santorum for voting for pet projects that often lard budget bills. "Earmarks are the gateway to corruption," McCain said. Rick Santorum sponsored earmark after earmark. LOOKING AHEAD: South Carolina voters got a peek Friday at new television ads that focus on values, one released by Texas Gov. Rick Perry and another by a group backing former Pennsylvania Sen. Rick Santorum. Perry's ad emphasizes his humble beginnings and service in the Air Force, while the ad released by a group backing Santorum calls their candidate "the principled conservative ... the conservative we can trust." BY THE NUMBERS: The latest TIME/CNN/ORC poll was a sobering one for Mitt Romney's rivals in South Carolina. The former Massachusetts governor has 37 percent support, a 17-point gain since early December. Rick Santorum was at 19 percent, a 15-point surge, and in a statistical tie with Newt Gingrich, who plummeted from 43 percent support. Five of the six contenders for the Republican presidential nomination campaigned in New Hampshire on Friday. Romney, Santorum, Huntsman, Paul and Gingrich crisscrossed the state, meeting voters. The state's primary is Tuesday. Romney was also looking ahead to South Carolina's Jan. 21 primary, campaigning in that state with Gov. Nikki Haley and Sen. John McCain, R-Ariz., the party's 2008 nominee. Only Texas Gov. Rick Perry stayed off the trail Friday. President Barack Obama had a power lunch with the not-so-powerful Friday. He and four winners of a contest for those who contribute small sums to his campaign - the suggested donation to enter was $3 - gathered at a trendy, Asian-inspired restaurant in Washington. The winners included a teacher and an Afghanistan war veteran. The Obama re-election campaign has offered the meals with the president, first lady Michelle Obama and Vice President Joe Biden to boost online contributions.