At the event, in Delaware, Biden raises worries of a GOP re-takeover of the House of Representatives. This story, in Roll Call, details the supposed vulnerability of three Arizona Dems:

Democratic members of Congress hold 49 districts that McCain won in 2008, including three in Arizona. Giffords’ district and that of Rep. Harry Mitchell (D-Ariz.) gave McCain 52 percent of the vote; Rep. Anne Kirkpatrick (D-Ariz.) won despite McCain taking 54 percent of the vote in her largely rural First District.
[…]
The fundraiser, held in Greenville, Del., will benefit Giffords’ bid for a third term. Giffords beat state Sen. Tim Bee® by a 55 percent to 43 percent margin in 2008, as both parties spent heavily on behalf of both candidates.

It doesn’t pay to argue with Roll Call on political matters, But I don’t think the argument applies quite so strongly to the Arizona delegation. McCain’s results here were outsized because of his favorite son status. And in the event, of the three only Mitchell got less than 55 percent of the vote.

Right now it’s entirely to the Democratic’s advantage to have hyperbolic worries like this come into play. It’s best to be in trouble—or look like you’re in trouble—14 months out. The party has an entire year for the impact of the presumed health care reform sink in and the economy to be on firmer ground.

The ruling party is always supposed to suffer in the first mid-year elections; the Democrats could take hits in the off-year New Jersey and Virginia governor races in November; and of course new troubles, like Afghanistan, may come to the fore and strain the administration’s ability to lay the blame on the mess on the previous administration. (Where it of course belongs.)

But given the ebb and flow of political difficulties I think the Democrats can only be happy what seems like a major ebb is happening this far out from the next round of elections.