Obama widens his lead in polls. So why does it feel like he's in trouble?

President Obama is defying political gravity – pulling ahead of Mitt Romney, even as pessimism about the economy grows. The question is, how long can he keep it up?

According to the latest NBC News/Wall Street Journal poll, President Obama has widened his lead over rival Mitt Romney. He’s now six points ahead (49 to 43 percent nationwide), up from a three-point lead (47 to 44 percent) last month.

In the key swing states, Mr. Obama’s doing even better. NBC/WSJ has him leading by eight points in the top 12 battlegrounds.

This is good news for the president. So why does it feel as if he’s in a tougher spot than he’s been in for much of the campaign?

Well, the poll shows Obama’s negatives are up, as are Mr. Romney’s – a result of the attack ads that both sides have been running. Even there, however, the numbers look worse for Romney, who, the poll points out, would be the only modern nominee to have a “net negative” favorability rating (meaning more people view him unfavorably than favorably).

No, the really scary poll number for Obama is this one: Only 27 percent of voters think the economy will improve over the next year. That’s down eight points from last month. And that level of economic pessimism is very dangerous for an incumbent.

In fact, it seems almost incredible – the political equivalent of defying gravity – for Obama to have gained ground in the horse race even as Americans’ views on the economy have grown increasingly, alarmingly, sour.

The question is whether Obama can continue to defy gravity like this all the way to November. Given the strikingly strong levels of dislike for Romney – who trails Obama by 20 points on likability in the poll – the president may still be able to stay on top. But we can’t imagine it will continue to be this easy.

In coming days, Obama will have to deal with yet another jobs report that’s likely to be less than inspiring – and this time, he may not be able to turn the media focus onto Romney’s business record and taxes as an alternate story line. And the Obama campaign is clearly still worried about fallout from the president's "you didn't build that" gaffe – as evidenced by the fact that they’ve released a new ad directly addressing it. (Note: When the president has to say in a commercial, “Of course Americans build their own businesses,” that’s not a good sign.)

Obama’s also going to be competing more and more with the “veepstakes” frenzy, as speculation about Romney’s running mate mounts, giving the Romney campaign plenty of free – and probably mostly positive – media.

And who knows what sort of “October (or September or August) surprise” may lie ahead to complicate things further for the president.

A few other interesting tidbits from the NBC/WSJ poll:

• Obama is getting more blame than Romney for running a negative campaign – with 22 percent saying he is, versus 12 percent saying Romney is (though 34 percent fault both candidates).

• It looks as if Romney has made some progress when it comes to one aspect of his image – “flip-flopping.” Last fall, Obama held a 14-point lead over Romney on “being consistent and standing up for his beliefs.” Today, that lead has shrunk to just two points (Romney has gained ground and the president has lost it).

• The percentage of voters who regard Obama’s health-care law as a “good idea” has reached its highest point yet, at 40 percent (though that still trails those who regard it as a “bad idea,” at 44 percent). Thirty-one percent now feel “strongly” that it was a good idea, up from 25 percent last month.