Santorum pledges to stay positive, behind the scenes goes negative LINCOLN PARK, Mich. - It was a day of contrasts for Rick Santorum. In a span of 24 hours, the former Pa. senator's campaign unleashed an attack on chief rival Mitt Romney to try to neutralize thousands of dollars in negative ads Romney is running against his chief threat in Tuesday's Michigan primary, while Santorum himself said he wanted to put all the negativity behind him and go "positive." "We're starting again here tonight and we will finish this campaign on a high note, on a positive vision and a winning one for America," Santorum told a relatively small audience of a little over 100 that turned out to see him on a snowy Michigan night. His speech, billed by the campaign as a "major announcement" of Santorum's economic agenda, was a reordering of his previously released economic agenda to highlight the steps he would take in his first 100 days as president. He said his priorities are: Cut $5 trillion in government spending in 5 years; repeal President Obama's health care law; approve the Keystone pipeline to bring oil from Canada to U.S. refineries; and eliminate regulations approved by the Obama administration. Santorum said he would also cut corporate taxes to 17.5 percent, and talked about the need to support American families by promoting marriage and two-parent families. "There's a difference between me and the left," he said. When I talk about the importance of building strong families, I don't necessarily mean that we need to have a government program to do it. But we do need to have a discussion about it. Left out of his address was a laundry-list assault on Romney's record, which was disseminated by Santorum's campaign staff earlier in the day. It included criticism of Romney's health care plan as governor of Massachusetts and his support for the Wall Street financial industry bailout and "liberal activist judges." His campaign also released an ad on Thursday (watch below) to run statewide in Michigan that hits Romney for not being a true conservative, highlighting his past comments to "preserve a woman's right to choose," and newspaper headlines about his approval of new taxes and fees as Massachusetts governor. In his remarks, Santorum did take Romney to task for his proposal to limit tax deductions on charitable giving for the wealthiest Americans. You want to talk about torpedoing the very civic institutions that make America work at the grassroots level? You just take their money away, you take the incentives for people to be generous to them," Santorum said. Andrea Saul, Romney's spokesperson, shot back with this statement: "Rick Santorum is a Washington insider who is lashing out at Mitt Romney because he had a terrible debate performance. Back in 2008, Senator Santorum endorsed Mitt Romney for president because of Mitt's 'conservative' record. Now, Rick's changed his tune. This sounds like another case of Rick Santorum abandoning his principles for his own political advantage.