Barack Obama has a 51 percent to 41 percent lead over Hillary Clinton when it comes to who Democrats would like to see win the nomination, according to a Washington Post-ABC News poll conducted April 10-13. But perhaps the most damaging news for Clinton is how negatively she is now seen.(Here’s the Post story, and for you data hounds, here’s the raw poll.) The poll, which has a 3 point margin of error,represents a 3 point gain for Obama since the beginning of March. A Gallup daily tracking poll yesterday also had Obama up by 10.

Clinton is seen unfavorably by 54 percent of voters compared to 40 percent who have a positive view, compared to the 58 percent who regarded her favorably in January. Obama is looked on favorably by a 56 percent to 39 percent margin, while John McCain has a 53 percent to 40 percent rating. The favorability numbers for Obama and McCain have also slipped, but not as precipitously as for Clinton. When Democrats were asked which of their candidates was more honest and trustworthy, they chose Obama by 53 percent to 30 percent. Obama’s lead over Clinton on this measure in January was 38 percent to 30 percent with John Edwards, then still in the race, getting 16 percent.

Forty-one percent of Democrats said the tone of the campaign has been negative and, when asked who was more to blame, they answered Clinton by a 52 percent to 14 percent margin.

In general election match-ups, the poll shows a close contest with McCain facing either candidate. Obama leads him 49 percent to 44 percent while McCain leads Clinton 48 percent to 45 percent.