At first glance, President Obama's partisan speech last week attacking GOP budget proposals was precisely what an incumbent running for re-election shouldn't do. It was not a speech designed to appeal to independent voters, a group Mr. Obama has suffered serious erosion with.

But Mr. Obama's tone makes more sense when one realizes that his sinking poll numbers also indicate an erosion in support with his liberal base. Only about three-quarters of self-identified liberals approve of his job performance, a number that has drifted downward since Mr. Obama compromised on tax cuts and decided to keep Guantanamo open. His latest budget deal with House Republicans only further confused his base. "I have been very disappointed in the administration to the point where I'm embarrassed that I endorsed him," one senior Democratic lawmaker told the Daily Beast last week.

John Fund previews an unlikely Texas Senate match-up and other 2012 election contests.

Mr. Obama is also hurting with another key element of his coalition: Hispanics. His job approval with them is now only 54% in the latest Gallup poll, down from 73% two years ago. Similarly, voters under the age of 30 give him a tepid 55% approval rating.

Obama strategists thought they had dodged a bullet earlier this year when it became unlikely the president would attract a serious primary opponent like Howard Dean or former Sen. Russ Feingold. But now it's clear that Mr. Obama has to worry that a dispirited liberal base could stay home in 2012, or that a spoiler third-party candidate could drain votes away from him the way Ralph Nader did with Al Gore in 2000.

The more that Mr. Obama feels he has to haul out class-warfare rhetoric and avoid offering serious proposals to stave off a fiscal crisis, the more he is endangering his standing with independent voters who remain unsettled by a sluggish recovery. The latest Gallup Poll pegs Mr. Obama's support among independents at just 35%. Right now, Mr. Obama is more concerned with shoring up his liberal base than with wooing independents. That's a sign of weakness.
