What happened
Candidates for the Republican presidential nomination dropped the friendly tone of the last debate and traded attacks as the polls opened in Florida’s closely watched primary. Mitt Romney and John McCain—who are in a tight race for the lead in the state—launched radio ads attacking each other, with Romney accusing McCain of being soft on immigration, and McCain calling Romney tax-happy and unelectable. (Chicago Tribune)

What the commentators said
It looked for a while that a “kinder, gentler” Republican field was emerging, said Brian Montopoli in CBSNews.com. “Fat chance.” As the crucial Florida primary approached, the candidates—especially the front-running duo of McCain and Romney—have traded “accusations of flip-flopping, liberalism and lack of leadership.” Former New York mayor Rudy Giuliani has been unscathed, but that’s just because nobody regards him as a threat any more.

The conventional wisdom used to be that McCain would lose if the race became a referendum on him, said Dean Barnett in The Weekly Standard’s Worldwide Standard blog. But even Republicans who “have no desire” to see him as the nominee are willing to forgive him for straying so often from the party line, thanks to his support for the Iraq war and “his admirable life story.” If Romney supporters want to win, they’ll have to make stronger points for their guy—not just against McCain.

McCain scored some points when he falsely accused Romney of wanting to set a timetable for withdrawing from Iraq, said syndicated columnist Jack Kelly in RealClearPolitics. It was “a low blow,” but it worked—changing the conversation from economics to national security, McCain’s strong suit. But in the final analysis, “both Sen. McCain and Gov. Romney are too flawed to reunite and reinvigorate a dispirited Republican party. There is only one candidate who can do that. And she might lose to Barack Obama.”