Mitt Mutes Newt

John Dickerson writes at Slate:

Newt Gingrich once reportedly said that "one of the great problems we have in the Republican party is that we don't encourage you to be nasty." No danger of that anymore. Romney has won back the front-runner slot through a relentless assault on his rival. After South Carolina, the Romney team decided to leave no Gingrich attack unanswered. Privately, they describe Gingrich as a bully who can't take a punch. "He's never won an exchange that hasn't been with a member of the press who can't fight back," said one.
...

The Romney campaign was trying to get into Gingrich's head, and it appears to have worked. In South Carolina, voters said Gingrich spoke to their conservative heart. Romney advisers say the 22-point switch in polls in the state took place after Gingrich's extended tussle with Juan Williams over racial sensitivity. "Williams was a stand-in for Barack Obama in people's minds," said one Romney adviser. Gingrich didn't repeat that performance during the Florida debates, and all of his other time was spent answering charges from Romney or complaining about them. He was also buried under negative ads, outspent by five to one. All of this effectively rendered him mute. What little space was left, Gingrich botched, driving himself off message by pushing the idea of a lunar base.