If Obama’s bounce fades over the next week, today might stand out as the day when the polls began to shift back in Romney’s direction.

After yesterday’s triumvirate of NBC/WSJ/Marist polls, today’s state polls show a tight race. Perhaps most surprisingly and importantly, SurveyUSA shows Obama up by just 1 point in Colorado, even though their other state polls have shown Obama leading by nearly ’08-esque margins in the blue states and the battlegrounds. By that same standard, we might have expected Obama up by at least 5 points, since he won by 9 in 2008. 

The big news might initially seem to be a CBS/NYT poll that provided some mixed news. On the one hand, Obama made a 8 point gain among registered voters since their pre-convention poll. But CBS/NYT applied their likely voter model for the first time and found Obama with just a more modest 3 point lead, although he still held 49 percent of the vote. Ultimately, a 3 point lead with 49 percent of the vote is largely consistent with the other post-convention polls, so it's not the big newsmaker it might have been a few days ago. In an average of post-DNC polls, Obama leads by 4 points, 48.8 to 44.4 for Romney.

Gallup also tilted back further in Romney’s direction, with Obama falling beneath 50 percent in Gallup’s polling. On the other hand, Obama retained a 49 percent approval rating in Gallup, suggesting that he’s held relatively steady at elevated levels over the last few days, even if not quite at his post-DNC peak. On the other hand, the Reuters-Ipsos internet tracker showed Obama leading by 7 points among likely voters, his best showing yet.

Rasmussen showed Romney reclaiming his pre-convention lead of around 3 points, but as I said yesterday, firm party-ID weights complicate their ability to accurately measure bounces. Imagine, for example, if some share of Democratic-leaning independents decide to describe themselves as “Democrats” following the DNC. This type of temporary shift in party-ID would be beaten out by Rasmussen’s weights, and the corresponding “bounce” might be as well, since the now over-weighted independents would include a disproportionate share of Republican-leaners.

Rasmussen did show Obama leading Virginia by 1 point and trailing in North Carolina by 6. Neither is especially surprising, although the Virginia tally looks decent for Obama compared to Romney’s 3 point lead nationally.

On balance, today's polls pointed toward a narrower Obama lead than surveys had shown over the last few days. If one had assumed that Obama's up 4 or 5 points nationally, then none of the battleground state polling would have lived up to your expectations. And of the national polls, only the Reuters/Ipsos and Zogby internet polls showed Obama holding his own. Next week, polls could return to showing Obama up by 5 in states like Colorado, Virginia, and Michigan. But if they don't, today might stand out as the day Obama's bounce began to fade.