The Republican presidential candidates repeatedly bashed each other's records this week, ahead of Thursday night's debate in Florida, a crucial swing state. Indeed, there will be "high stakes" for frontrunners Rick Perry and Mitt Romney — and for rivals struggling to keep their hopes alive — as the showdown in Orlando sets the table for a Saturday straw poll that leading Sunshine State Republicans say will predict the party's 2012 nominee. What should viewers watch for when the candidates square off on stage Thursday? Here, four key questions:

1. Can Romney take down Perry over Social Security?
Watch for Romney to really tear into Perry for calling the federal retirement program a "Ponzi scheme," says Curt Anderson for the Associated Press. Romney has been hammering the issue all week, insisting that Social Security is here to stay, and that Perry's insistence that states should take it over "does not work in any way, shape, or form." So far, GOP voters in retiree-rich Florida haven't been scared off by Perry's rhetoric, but still, look for the Texas governor to counter Romney aggressively: Already, a Perry campaign spokesman accused the former Massachusetts governor of "sounding like a Democrat."

2. Which Rick Perry will take the stage?
The Texas governor said he felt "like a pinata" in his first debate, on Sept. 7, says Maggie Haberman at Politico. But that night, Perry certainly gave as good as he got. However, in his second debate, we all watched Perry "barely putting up a fight as Michele Bachmann ripped him over his mandate of an HPV vaccine for young girls." Which Perry will show up Thursday — the "polished," confident candidate ready to counter expected attacks from Romney on Social Security and Ron Paul on immigration; or the "ill-prepared" and "fatigued" Perry who got pummeled for two hours at the CNN/Tea Party Express scrum last week in Tampa?

3. Can Gary Johnson make a difference?
Fox News and Google — co-hosts of the debate — will give former New Mexico Gov. Gary Johnson a spot on the stage because he met the qualifying standard of cracking 1 percent in a national poll. H
is presence could help Perry and Romney, says Howard Kurtz at The Daily Beast, if only because the "quirky" Johnson — a libertarian who supports legalizing marijuana and opposes a border fence to stop illegal immigrants — will be "diluting the airtime available to the other contenders" looking to take the frontrunners down.

4. Will second-tier candidates break through?
The frontrunners' struggling rivals will use the debate to "try to find a foothold" in what is fast becoming a two-candidate race, says Patrick O'Connor in The Wall Street Journal. The three-day GOP extravaganza in Florida could "separate out the wheat from the chaff," says Republican pollster Alex Patton, as quoted in The Miami Herald. Florida's last three straw polls have picked the winner of the GOP nomination. "You're going to get a week, week and half of coverage from this debate and vote." Whoever gets that publicity will score fundraising advantage, momentum, and name recognition. Newt Gingrich, Ron Paul, Michele Bachmann, Herman Cain, Jon Huntsman, and Rick Santorum all poll in single digits. This debate could be the last chance for many of them to remain relevant.