When it comes to the chances of a Dem "dream ticket"--Hillbama, if you will--hope springs eternal for some:

Mario Cuomo, former governor of New York, has pressed the idea most aggressively--it also came up in last week's debate--while a major Clinton supporter in the Pennsylvania primary, Governor Ed Rendell, has blessed it, too.

And some uncommitted superdelegates--the party leaders and elected officials whose votes may determine the nominee--see such a unity ticket as a way to short-circuit a fight for the nomination all the way to the Democratic convention in August, and to blend the voter bases of the two candidates.

"It would be great to see them on the same ticket--they had attracted so many new voters and so much excitement, it seems so obvious," said Sam Spencer, an uncommitted superdelegate from Maine.

Bitter rivals have united in the past, but this week's ego contest seems to diminish the odds of it happening this year.

All that stands in the way are a few pesky details--like that Obama and Clinton want to be done with each other, starting now. And that Bill Clinton bitterly believes that the Obama camp has portrayed him as a brutish and race-baiting campaigner, according to two associates of Clinton. On top of that, Obama aides assert, Senator Clinton's baggage would damage Obama's image.

To be precise, aides for both candidates would not rule out the idea of a joint ticket - though it was hard to hear it through all the laughing.