ROCK RAPIDS, Iowa - Leaving his second campaign event on New Year's Day, Rick Santorum responded to a dig thrown his way by the campaign's front-runner, Mitt Romney, who Sunday called him a "career politician."

"It's just pretty funny," Santorum told ABC News as he left his event in Orange City. "I mean, I didn't spend my entire career, I worked as a lawyer, I worked in private sector working in a small technology company for three years and done other things in the private sector, been on corporate boards and managed those things. So Gov. Romney suggests that if you've served three terms in the House and two terms in the Senate because you won elections where he has not won elections that somehow or another you are a career politician."

He said being in the front-runner's sights "suggests we are on the move."

"We are resonating with the people of this state and I think we are going to resonate with the people of this country because I think we reflect the values of the people a lot better than the folks in the field, at least I hope that's the case," Santorum said.

At his three events Sunday, Santorum was excited, enthusiastic and clearly buoyed by Saturday night's Des Moines Register poll that showed the former Pennsylvania senator surging in the final two days of polling. At Romney's event Sunday in Atlantic, Iowa, he compared Santorum to Newt Gingrich's aiming to paint them both as lifelong politicians.

"Like Speaker Gingrich, Sen. Santorum has spent his career in the government, in Washington; nothing wrong with that, but it's a very different background than I have, and I think that the people of this country recognize that with our economy as the major issue we face right now that it would be helpful to have someone who understands the economy firsthand, who's spent the bulk of his career working in the private sector," Romney said, adding that his new rival "has worked hard. I wouldn't be surprised if we see him do well on Tuesday night."

Crowds throughout the day were enthusiastic and much bigger than those that have turned out for Santorum on the trail.

In Orange City, more than 200 people sat in the basement of a bank to listen to the candidate.

As he gave his closing argument to voters, he told them about his grandfather who immigrated to America from Italy. He often mentions him on the stump, but Sunday he seemed emotional, choking up while giving the final pitch.

"Do not miss, do not miss. This country is too important," Santorum said.

At Santorum's first event in Sioux City, two of the men introducing him, talk radio host Sam Clovis and author Brad Thor, broke down in tears when speaking about why they are backing Santorum.

For the second time in two back-to-back events, he was asked by a supporter what to say to friends who don't like him because of the candidate's 2004 Senate endorsement of Arlen Specter over the more conservative Pat Toomey.

In Orange City, Santorum repeated his defense: he did it to ensure Specter's support to confirm President Bush's Supreme Court nominees.

It's an issue he's had to deal with here throughout his campaign. Anonymous groups often place fliers in cars at his events connecting the two. Friday, a flier placed in cars in Ames called the strident anti-abortion rights supporter a "pro-life fraud."

In Rock Rapids, Santorum was again greeted by a packed room with about 150 voters in another bank basement. Santorum spoke and took questions for almost two hours and told the crowd the country needs a "clear contrast conservative."

"We need dramatic change in Washington," Santorum said, stressing that voters "can't settle" for the candidate that others may think is more electable, but is too similar to President Obama. Although he didn't mention Romney by name, he was clearly referencing him.

"We need bright, bold colors, not pale pastels," he said, repeating a phrase of Ronald Reagan's, pitching himself just two days before the caucuses that he's the only candidate who can bring that dramatic change to Washington.