The poll, published Wednesday, said 48 percent of registered voters said they were more likely to vote for Obama, D-Ill., with 42 percent backing Sen. John McCain, R-Ariz., and 6 percent still undecided, CBS said.

But the poll contained some good news for McCain as well. Some 12 percent of Democrats surveyed said they would back McCain, giving him 150 percent more support from Democrats than the 8 percent of Democrats who backed U.S. President George W. Bush in 2004 four years ago.

Also, the poll confirmed McCain's attraction to centrists: He scored an 8-point advantage over Obama among registered independent voters, it said.

And the poll also pointed to the urgency of Obama's reconciliation summit with Sen. Hillary Clinton, D-N.Y., to heal the wounds that tore the Democratic Party apart during the long, bruising primary and caucus contests that raged from Iowa in January and that only ended this week. Some 59 percent of Democratic primary voters told the pollsters Obama ought to pick Clinton as his running mate.

Historically, approval and disapproval ratings for front-runner candidates for both parties often fluctuate wildly across the summer and only settle down -- and often get set in stone -- after the parties conclude their national conventions. Nevertheless, the CBS poll points to a number of key developments that we expect to remain central throughout the next five months of the campaign.

First, the Dems above all need to heal their wounds and close their ranks. If they Can Do this, they vastly increase their chances of winning in what is already shaping up to be a cataclysmic election year for congressional Democrats -- and we predict here that it may be the worst for the GOP on Capitol Hill since Lyndon Johnson's election in 1964.

The poll pointed to this by noting that President Bush's approval rating had now fallen to 25 percent -- the lowest CBS polls have recorded him at in his entire seven and a half years in office and dangerously close to Harry Truman's abysmal basement-level approval standings in 1952 -- the year GOP candidate Gen. Dwight Eisenhower swamped Illinois Gov. Adlai Stevenson. Bush's disapproval rating was at 67 percent, also a record for CBS polling.

The current standing of McCain shows he has already done remarkably well in distancing himself from the president and establishing himself as his own man. Given the field from which the Republicans had to choose, this also confirms our analysis half a year ago that McCain represented not only the best, but probably the only chance the Republicans had of retaining the White House this year.

But the poll also contained findings that explained why Obama, a first-term senator with only a fraction of McCain's experience, is already running ahead of him with a 6-point lead -- already outside the traditional 5-point "margin of error" or "too close to call" category -- so early in the race.

Fully one-third of those surveyed said the U.S. economy remained their biggest worry, while more than two-thirds -- nearly 70 percent -- said the economy was deteriorating. Only 3 percent said it was getting better. The great tidal wave of economic booster-ism that Bush rode for so long has now vanished.

Even worse, after seven and a half years of a partisan, confident and aggressive conservative administration that was backed for almost all the first six of those years by a Republican-controlled House of Representatives and Senate, 83 percent of those polled expressed concern that the United States was going in the wrong direction. This was the highest percentage expressing pessimism -- in a traditionally optimistic nation -- since CBS pollsters first put the question on their lists a quarter-century ago.

Overcoming these numbers is the Herculean task that grizzled old Navy aviator Top Gun McCain has set for himself. He has always been at his most formidable and best when attempting Mission Impossible. He has one now.