PPP does us a big favor by throwing in both congressional districts (both of which are tossups this year) in with their statewide poll of the Senate and gubernatorial races. We've already gotten a sense that these races are potential trouble thanks to a UNH poll from February; the generally more trustworthy PPP finds Dems in better shape in the 1st (where UNH saw Rep. Carol Shea-Porter losing 43-33 to former Manchester mayor Frank Guinta... although bear in mind that UNH saw Shea-Porter losing through most of her first re-election in 2008) but Dems faring even worse in the 2nd.
There's not too much falloff in Democratic enthusiasm in these districts; their samples went 48-45 for Obama in the 1st and 52-46 for Obama in the 2nd. Instead, there seems to be some antipathy to the Democratic candidates in these districts; Shea-Porter's approval is 41/50, and Swett fares even worse, somehow managing to be unknown and unpopular among those who know her: 19/29 (including, tellingly, 35/16 among liberals and 35/18 among Democrats). Shea-Porter is pretty much locked-in; her survival will be all about turnout and the Dems' overall standing come November. But it'd be interesting to see whether Ann McLane Kuster (who's probably even less known than Swett, but likely in better standing with the Democratic base) fares any better against Charlie Bass, who benefits from being fairly well-known, having held the seat from 1994-2006. Alas, there were no head-to-heads involving Kuster (or, in the 1st, involving the lesser GOPers).