It's pretty quiet on the polling front today. The only numbers out are the national trackers: Barack Obama now has a 6-point lead in Gallup, down from 8 points yesterday, and a 5-point lead in Rasmussen, a tick down from 6. These polls will not really reflect any happenings at the GOP convention, since Monday's events were essentially canceled, and since Tuesday's occurred to late in the evening to be reflected in most interviewing.

Even though Obama moved down slightly in the trackers, our projection model still has him gaining ground, as it still has some ground to make up before it "catches up" to the current numbers. This is by design: we don't want the model to overreact to a few days' worth of polling (until the very end of the election, at least, when we will tune it to be very aggressive).

Of course, the strong likelihood is that the next move will be in McCain's direction once the Republicans get a convention bounce of their own (if it isn't, the Republicans are in a lot of trouble). But all else being equal, I wouldn't expect the Republicans to get quite as large a bounce as the Democrats did. The reason is that Obama had a lot of low-hanging fruit to make up among white Democrats, among whom he moved up from 74 percent support to 82 percent support following his convention (per Gallup). I don't see Obama giving most of those points back. McCain, on the other hand, already had the support of something like 90 percent of Republicans, this number actually having increased a bit following the selection of Sarah Palin. I think McCain is likely to gain some ground among independents, however, and that the tracking polls will most likely wind up somewhere in the range of McCain +1 to Obama +3 over the weekend.

--Nate Silver