John & Elizabeth Edwards

Senator Barack Obama will be the Democratic presidential nominee, John Edwards told Bob Schieffer on “Face the Nation” on CBS this morning. “The problem is, I think, you can no longer make a compelling case for the math,” the former senator from North Carolina and two-time contender for the Democratic presidential candidate said on the Sunday morning talk show.

While not endorsing Barack Obama or calling for Hillary Clinton to withdraw from the race, Edwards did warn Clinton about running a destructive campaign in the last leg of the primary season, which includes six primaries, from West Virginia to Puerto Rico.

“I think the one thing that she has to be careful about - and she doesn’t need my advice, she knows this full well - is that, if she makes the case for herself, which she’s completely entitled to do, she has to be really careful that she’s not damaging our prospects, the Democratic Party, and our cause, for the fall,” Edwards said.

The North Carolinian made the comments in response to Schieffer’s question to Edwards asking him what he thought of Clinton’s controversial comments in a recent interview with USA Today, in which she said, “There was just an AP article posted that found how Senator Obama’s support among working — hard-working Americans, white Americans is weakening again, and how the, you know, whites in both states who had not completed college were supporting me.”