Santorum blasts Romney: "Who do you trust?" TOPEKA, Kansas -- Rick Santorum wants a one-on-one battle against Mitt Romney for the GOP nod -- and he's stepping up his attacks on the Republican frontrunner in the hopes that a two-man race is what he'll soon have. Billy Weeks - Reuters In an address to more than 200 supporters in the atrium of a train station here, Santorum used some of his most scathing rhetoric yet against Romney, blasting the former Massachusetts governor as a false conservative and taking aim at his record on health care, spending and other issues. As governor, Santorum argued, Romney was "for a government-mandated health insurance program. He was for adopting Romneycare as a national model. But in the 2012 campaign, he continued, Romney has disavowed his previous comments on the Massachusetts law. You know what, ladies and gentlemen? Santorum said. We already have one person who doesn't tell the truth to the American people. We don't need another. Governor Romney reinvents himself for whatever the political occasion calls for. He continued: "Trust. This election is about trust. Who do you trust? Romney spokesperson Andrea Saul responded in a e-mailed statement, "Washington insider Rick Santorum is lashing out at Mitt Romney because he can't accept the fact that it's nearly impossible for him to win the number of delegates needed to secure the Republican nomination . Four years ago, when he was speaking candidly, he said Mitt Romney would "stand up for the conservative principles that we hold dear." In comparison, Sen. Santorum admitted he "took one for the team" in Washington by voting against those principles. This is yet another case of Sen. Santorum abandoning principle for his own political advantage. The attack by Santorum comes even as former House speaker Newt Gingrich (R-Ga.) is insisting he'll remain in the GOP race, along with Rep. Ron Paul (R-Texas), who like Santorum is campaigning in Kansas ahead of Saturday's GOP caucuses. In the crowd at both Santorum's and Paul's Topeka events Friday was Kansas Gov. Sam Brownback (R), who had previously endorsed Texas Gov. Rick Perry (R) but is now neutral in the race. As Santorum recognized Brownback from the podium, the governor smiled, waved and opened up his suit jacket to reveal that he was wearing a sweater vest -- Santorum's signature item of clothing. In an interview after the event, Brownback said that he believes Kansas" nominating contest is "a very important one for Rick." "A Romney win here, I think, would be difficult for Santorum at this point in time," Brownback said. A Santorum win here I think really further solidifies his position as the alternative, probably, to Romney. Asked about the Santorum camp's contention that now is the time for a two-candidate race to take shape, Brownback -- who himself ran for president four years ago and ended up leaving the race as the social conservative vote began to coalesce around former Arkansas governor Mike Huckabee -- said that "it's getting close to that." "If you look at Tuesday night's results, it looked like ... really Santorum got a big purse, I thought, on Tuesday night," he said. Romney did well, I think as well, but when comparing where's your alternative candidate to Romney, it just seemed like Rick Santorum had a good night Tuesday night and he's probably got a lot of momentum out of that. What about Gingrich's big win in Georgia? "That's important, but you're kind of expected to win your home state," Brownback said. If you don't, that's problematic.