Ahead of Tuesday's Florida GOP primary, Mitt Romney hit Newt Gingrich with "one of the most expensive and sustained negative ad bombardments" Americans have ever seen. The consensus among political strategists is that the attack ads paid off, erasing Gingrich's polling lead and setting the stage for a Romney landslide. But critics warn that the blizzard of mud may ruin Romney's squeaky-clean image with the independent voters he'll need to beat President Obama in November. Will going negative backfire?

Yes. These attacks could really damage Mitt: Romney is paying a price for going negative, say Domenico Montanaro and Carrie Dann at MSNBC. His brawling with Gingrich "may be hurting his image with the general electorate" — his negative ratings among independents have shot up by 13 percentage points since December. If Romney does manage to wrap up the Republican nomination quickly, political strategists say he'll have to "pivot" quickly to start winning back the key swing voters he'll need in the general election.
"As primary war wages, Romney's support with independents dips"

But these negative ads worked: Romney's attack-fest is indeed "unprecedented," says John Avlon at The Daily Beast. His campaign and his loyal super PAC, Restore Our Future, have spent $15.3 million on ads in Florida — $4 million more than John McCain spent in his entire 2008 primary campaign — and 92 percent of the ads last week were negative. It's risky, but Romney has to beat Gingrich before he can challenge Obama. And the "tsunami of sleaze" has stopped Gingrich's momentum cold. 
"Romney ramps up attack ads against Gingrich to unprecedented levels"

And independents might respect the new Mitt: Romney's "willingness to campaign hard" has worked so well in the primaries, says David Swindle at PJ Media, that it makes you wonder whether it will pay off in the general election, too. A bit of "forcefulness from the generally more mild-mannered Mormon Mitt" might look better to an independent voter than a fit of "Gingrichian rage." One thing's for sure: The GOP primaries are no longer about who's the "true conservative"; they're about who's the shrewdest campaigner.
"Mitt Romney's Florida media war and the plan to beat Obama in 2012"