OK, this is one rotten poll for the president:

More than 4 of 10 likely voters who say they once considered themselves Obama backers now are either less supportive or say they no longer support him at all, according to a Bloomberg National Poll conducted Oct. 7-10.

Three weeks before the Nov. 2 congressional elections that Republicans are trying to make a referendum on Obama, fewer than half of likely voters approve of the president’s job performance. Likely voters are more apt to say Obama’s policies have harmed rather than helped the economy. Among those who say they are most enthusiastic about voting this year, 6 of 10 say the Democrat has damaged the economy. …

The erosion of backing for Obama among onetime supporters has been most notable among two groups of voters who were central to his election: women and independents. More than 6 of 10 of the former Obama backers who have turned away from him are women; 53 percent of the onetime supporters are independents.

Yikes. as Andrew Malcolm put it, “Other than that, his virtually nonstop cross-country campaigning for embattled Democrats in the Nov. 2 election is working perfectly.”

Obama has fused disparate groups into one giant not-Obama coalition. Unless he wants to reinvent himself, it’s hard to see how he can revive his presidency.