In 2010, I looked at early voting in 20 states and found early signs of the disproportionate Republican turnout that would define the Tea Party wave. This year, the picture is more mixed, befitting the sort of non-wave election most are expecting. It should shock no one that signs point to a significant dropoff from 2008 for Obama; if Election Day trends hold, he seems likely to lose a handful of states he won four years ago. In particular, the early vote looks promising for Republicans in North Carolina, Florida and Colorado. But early voting in Iowa, Nevada, and (though it's tricky to assess) Ohio still looks strong enough for Democrats.

This analysis isn't conclusive; it's a faint clue at best. But with as much as 40 percent of the nationwide vote likely to have been cast before the polls open on Tuesday, here's what the early vote is telling us so far.

(You can find all these numbers, updated daily, at the invaluable website maintained by George Mason University Professor Michael McDonald. I've listed the states that register voters by party first, followed by the iffier case of those that don't.)

COLORADO

Who's leading the early vote: Republicans, 38 percent to Democrats' 35 percent.

How significant is it: Very. Nearly 80 percent of voters voted early in 2008.

The spin: Democrats say they are leading among "non-midterm voters" who are voting early. But there's no getting around it: Republicans -- who lost the early vote in Colorado by 4 points in 2008 -- are winning it this time, and the early vote is a huge majority of the total vote in this state Obama won by 9 points in 2008.

Who's really winning: Republicans.

FLORIDA

Who's leading the early vote: Democrats, 43 percent to 41 percent.

How significant is it: More than 50 percent voted early in 2008.

The spin: Though Democrats are leading the combined early and absentee vote in Florida, they led it in 2008 by a much greater margin. Their current lead of nearly 60,000 votes is far short of the 280,000-vote lead (and 46-37 margin) they carried into Election Day in 2008. (The dropoff could be a result of the shortening of in-person early voting.) Republicans' share of the early vote, 41 percent, is 5 points higher than their share of voter registration, 36 percent, while Democrats' 43 percent of early voters is just 2 points above their 41 percent voter registration share. In a state Obama won by less than 3 points in 2008, where the majority of votes are early and Republicans tend to win Election Day, any falloff should be concerning for Democrats.

Who's really winning: Republicans.

IOWA

Who's leading: Democrats, 43 percent to 32 percent.

How significant: More than a third voted early in 2008.

The spin: Republicans note that Democrats surged to a 44-point lead in Iowa early votes in late September and have since seen it steadily whittled away. More Iowans of all parties are voting early than ever: Nearly 80,000 more votes have already been cast than 2008's total Iowa early votes. In 2008, Obama's 18-point lead in early voting enabled him to narrowly lose Election Day and still carry Iowa by nearly 10 points. Despite the decline in Democrats' margin, they are still likely have a pretty good cushion going into Nov. 6.