Louisiana Sen. David Vitter is running for governor, and he doesn't face any kind of election this year. Nevertheless, trackers at the liberal group American Bridge were on hand for one of his town halls, where they captured video of an exchange between the senator and a constituent who sounds nervous about lobbying money. She tries to discuss the "Kotch brothers," and botches the name.

"Koch brothers," says Vitter, correcting her pronunciation.

"They have paid so much money," says the woman. Vitter interrupts her.

"I think the Koch brothers are two of the most patriotic Americans on the face of the Earth," he says. There are cheers from the crowd. "I'll be honest with you. My reaction is: God bless the Koch brothers. They're fighting for our freedom."

This is, as giddy Democrats are pointing out, the most robust defense of the Republican mega-donors yet caught on tape. At CPAC, with many more cameras on him, Gov. Chris Christie came close to saying the same thing as Vitter, but referred obliquely to "two great Americans."

Now, Christie had been personally lobbied, by David Koch, to run for president. If he runs in 2016, he's going to need to rewire the networks connecting him to wealthy donors, the people who might have become nervous about "Bridgegate."

What's Vitter's angle? I don't immediately see one; I think it's something in the air. Harry Reid used two weeks of floor speeches to attack the Kochs and the ads being run against vulnerable Democrats. Republicans, at first, attempted to boomerang the attacks by saying Reid was attacking the innocent, real Americans who appeared in the ads. But it's not in their nature to be defensive; they're already working hard to portray pro-Democratic billionaires like Tom Steyer as rent-seekers who lack the free-market principles of the Kochs. They're tired of having to explain away support from two of the country's richest men.