Two Democratic pollsters, Pat Caddell and Doug Schoen, are urging Barack Obama not to seek re-election, in favor of letting Hillary Clinton run instead.

Their arguments are compelling.

1. That he can no longer govern effectively.

2. That his campaign will necessarily have to be negative and divisive.

3. That he has utterly failed in his promise to bring the country together.

But one of their talking points, at least from a Democratic perspective, should raise concerns. They sight two cases of Democratic presidents declining to run full second terms: Lyndon Johnson and Harry Truman. They don't mention that in both cases a Republican won the White House (Nixon, Eisenhower.)

Also they don't consider what forcing Obama to drop out of the race would do to the Democratic coalition, especially black voters. They would not doubt resent that the first African American president was forced from seeking a second term.

Still, there is no denying the problem for Democrats. Today's OWS protests are becoming reminiscent of the draft protests of 1968 that forced LBJ from seeking another term and paved the way for Nixon's comeback. To the extent that the protests continue and civil unrest grows, this will be a huge problem for Democrats and Obama.