TROY, Mich. — Mitt Romney leveled a string of stinging attacks on rival Rick Santorum at a tea party forum here Saturday, including questioning the former senator’s endorsement of Arlen Specter, a fellow Pennsylvanian, over more conservative candidates in the 1996 presidential race.


Romney campaigns in Detroit on Friday. (AP)

The former Massachusetts governor hammered Santorum about an hour after Santorum was on the same stage thundering that Romney had been unreliable as a conservative and that his inconsistency on key issues “disqualified” him from becoming the Republican Party’s standard bearer in the general election against President Obama.

By using an attack referencing the 1990s, Romney may also have reminded voters of his own moderate history. In 1994 and again in 2002, he ran for office in Massachusetts as a Republican a supporter of abortion rights. As governor, he changed his stance to become an opponent of abortion rights.

In his remarks here, Romney tried to demonstrate his conservative credentials by pledging to balance the federal budget, cut the deficit and repeal Obama’s health-care overhaul.

"I can attest to my conservative credentials by quoting someone who endorsed me in 2008 campaign,” Romney said. “Senator Santorum was kind enough to say on the ‘Laura Ingraham Show,’ he said, ‘Mitt Romney, this is the guy who is really conservative and who we can trust.’ …. He’s right. I’m the conservative candidate.”

Romney received polite applause from the crowd of more than 1,000 conservative activists, but it was not as overwhelming as the reception Santorum received earlier in the day.