Vice President Biden dipped a tentative toe into the touchy side of presidential politics when he addressed accusations from Republican candidate Newt Gingrich's ex-wife that Gingrich wanted an open marriage.

"I have no comment," the vice president said at first, in a radio interview with KIIS-FM Los Angeles Host Ryan Seacrest. The interview was recorded on Friday but aired Monday.

"Look, this is quick sand," he added after a slight pause."I think that Newt Gingrich is, as we all are, is gonna be judged by the voters in the primary in the totality of who he is and that includes everything. I mean, people make judgments about our character. They make judgments about our positions."

Gingrich has denied that he asked his wife for an open marriage and has repeatedly scolded other candidates for getting dirty in their political attacks.

The Obama campaign has so far preferred to let the GOP candidates duke it out when it comes to personal issues, but when Seacrest asked Biden his take on Gingrich's view that media scrutiny makes it tougher for decent people to run for office, Biden waded right in.

"Look, this is not an endeavor for the faint-hearted. But look, the sincerity meter of the American public is pretty well-attuned. I think the one thing that public punishes a public official for is if he or she turns out to be different than they advertised themselves to be," he said.

"And by the way, we don't have to answer every question we're asked. We may get penalized for not answering. That's for the public to judge, but it's-- you know, it's it's-- If you can't stand heat, you shouldn't be in kitchen."