The Vice Presidential trial balloon of the week seems to be Joe Biden. Coming on the heels of Evan Bayh, he seems like a huge relief to many, but it may be one of those situations where you feel better simply because you stop hitting your head against the wall.

Nate Silver notes that in a recent poll, Biden’s strong unfavorables exceed his strong favorables:

Basically, I think he is identified enough with the (unpopular) institution of the Congress that he will be viewed by a lot of people as a partisan, but doesn’t compensate for that by generating enthusiastic responses from the base, the way some other candidates might. Biden is fairly well-known — by far the best know candidate of the Bayh/Biden/Kaine/Sebelius group — so perceptions of him are liable to be fairly entrenched, and may not be enhanced by the fluffy sort of treatment that the VP candidate usually tends to get from the press.

On the plus side, Nate says Biden could shore up Obama’s numbers with old people and moderates, and he may well lock up Pennsylvania for him.

A lot of the Vice Presidential choice’s value boils down to chemistry — and Obama and Biden very well may have it. But Biden voted for the AUMF and the Patriot Act, so all those who thought a VP who "undermined Obama’s message of change" would just not be acceptable will no doubt be uncontrollably vexed. Or not.

Then there’s the problem that Biden has a history of saying really stupid stuff. Which could turn out to be a plus I suppose, if he draws the flies off Obama.

An unusual election strategy, to say the least.