ORLANDO, FLA. - Presidential candidate Michele Bachmann went into Thursday night's GOP debate looking for an opening to crack into what now seems to be a two-man race between the new conservative powerhouse, Texas Gov. Rick Perry, and the business-minded, establishment favorite Mitt Romney.

The Minnesota Republican found a few chances in the interactive Fox News/Google debate, which mingled questions from YouTube viewers with an array of sharp attacks between the two top contenders.

In one of the toughest exchanges of the night, Romney accused Perry of running away from his hard-line critique of Social Security. "There's a Rick Perry out there that's says the federal government shouldn't be in the pension business, that it's unconstitutional, that it should be returned to the states, so you better find that Rick Perry and get him to stop saying that."

Perry fired back at Romney's alleged flip-flops on a number of issues, from abortion to the health care plan in Massachusetts, which was the model for what Republicans deride as Obamacare. "I think Americans just don't know sometimes which Mitt Romney they're dealing with," Perry said.

Bachmann joined the fray mostly in taking issue with Perry, who has eaten into much of her Tea Party support in the race.

She revived her attack on Perry's health care record in Texas, where he once sought to mandate the HPV vaccine to protect pre-teen girls from a sexually transmitted virus that can cause cervical cancer. On the stump, Bachmann has been coupling her critique with a charge of "crony capitalism," a reference to Perry's ties to HPV vaccine maker Merck. Perry has deflected the issue by casting it in abortion opposition terms, although he acknowledged in last week's CNN debate that his executive order had been a "mistake."

Bachmann came to the Orange County Convention Center needing to live down two television interviews where she tried to link the HPV vaccine to mental disabilities. She also needed to check Perry's appeal within her conservative Christian base of support, a dynamic that has cost her severely in Florida and elsewhere.

'End the madness'

Bachmann and Romney also ganged up on Perry over immigration, an issue that has hurt the Texas governor with conservatives because of his support for educational benefits for the children of illegal immigrants, and his opposition to a border fence.

"End the madness for illegal aliens to come into the United States of America," Bachmann said.

The sixth nationally televised debate of the GOP's 2012 nominating contest was viewed by political analysts as a potential endpoint for some of the nine candidates who participated, with Republican activists starting to coalesce around a shrinking circle of top tier contenders. But there were no knock-out blows, and the final minutes of the debate grew cordial, as the candidates joked about possible vice presidential candidates. The other participants were Rep. Ron Paul, former Utah Gov. Jon Huntsman, former House Speaker Newt Gingrich, former Sen. Rick Santorum, pizza magnate Herman Cain and former New Mexico Gov. Gary Johnson.

While all the GOP contenders were critical of Obama, Romney declined to repeat Bachmann's contention that he's a "socialist."

"What President Obama is is a big-spending liberal, and he takes his political inspiration from Europe," Romney said, aiming for a more measured tone.

Amid the give-and-take between Romney and Perry, Bachmann at times had to force her way into the debate, jumping in at one point to express her opposition to commercial flights between the U.S. and Cuba. She also vowed that as president she would "turn off the lights" in the Department of Education and return federal education funding to the states. Pressed on her strong religious views, Bachmann said that while she believes in freedom of conscience, "that doesn't mean that we aren't people of faith, or that people of faith shouldn't be allowed to exercise religious liberty in the public square."

'Don't have to settle'

Given Bachmann's inability to capitalize on her win in last month's Iowa straw poll, campaign consultant Ed Rollins has suggested an Iowa-centric strategy that would play to her strengths among evangelicals and other Christian conservatives.

While frontrunners Romney and Perry have been emphasizing their electability before groups of Republican voters, many of whom are increasingly focused on beating Obama, Bachmann has doubled down on her image as a socially conservative purist.

Hours before the debate, Bachmann thrilled fans at a rally of Ralph Reed's Faith and Freedom Coalition in Orlando. She quoted scripture and highlighted her efforts to pass a constitutional amendment banning same-sex marriage in Minnesota. "Of any election, this is one where conservatives don't have to settle," she said. "We don't have to sit in the back of the bus in this election."

Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.

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