Republicans continue to be on pace to exceed their early voting performance from 2008, though Democrats still lead in most of the important states.

Here's the latest breakdown on our Early Voter Tracker:

(Big thanks to the United States Elections Project for the data used above and below.)

A couple updated trends since our last update:

* Lots and lots of people have now voted early. In Nevada, the number of people casting ballots is already half of the state's entire 2008 turnout. In North Carolina, it's 43 percent. And in Colorado, Iowa and Florida, it's between 30 and 40 percent of the total 2008 turnout.

This serves as a reminder that the presidency isn't won on Election Day; it's determined in very large part by the people who have already cast ballots.

* Democrats' leads in Nevada, North Carolina and Iowa continue to shrink. Even as Democrats will assuredly turn out more early voters in all three states, they are on pace to gain less from early voting than they did in 2008.

Democrats have some cushion in Iowa and Nevada, where they won in 2008 by 10 and 12 points, respectively (more on that here). But they won by less than 1 percent in North Carolina, so the fact that they are behind their early-voting pace from four years ago could bode well for the GOP.

* Thanks to the start of in-person early voting in Florida, Democrats there have gained an advantage. While the GOP built an edge earlier this month on absentee ballots, Democrats have eclipsed that with the start of in-person early voting.

That said, Democrats hold a narrow lead (43 percent to 41 percent) and are not on pace to match their 46-37 advantage from 2008. We are through four days of the eight-day period for in-person early voting, and while Democrats gained big on the first two days (Saturday and Sunday), they were unable to keep that pace on Monday and Tuesday. Democrat netted 73,000 vote from the first two days, but gained 28,000 votes on Monday and just 16,000 votes on Tuesday. Meanwhile, Republicans keep building their absentee lead, which stands at 70,000 votes.

While Democrats won the combined early vote (absentee plus in-person) by more than 360,000 votes in 2008, they currently lead by about 49,000. That edge will grow over the next four days as Democrats build their in-person early voting lead (many more people vote in-person than absentee), but it's unlikely to approach anywhere near 360,000.

* The one state where Republicans have a clear lead is Colorado, where 38 percent of early votes have come from Republicans and 36 percent have come from Democrats. That said, Democrats had just a two-point early vote advantage in 2008 and still won the state by nine points overall.

* Ohio, as usual, is harder to measure, since the state doesn't have traditional party registration. Polling last week showed Obama winning the early vote by between 26 and 30 points. A new CBS News/New York Times poll shows his advantage at 26 points and an automated SurveyUSA poll shows that margin is down to 16. A late Friday poll from CNN showed Obama winning by 21 among people who already voted or planned to vote early.

The polling suggests that Obama is clearly building an early vote advantage in Ohio, even as we don't have the party registration numbers to back it up.

* In Virginia, early voting isn't as big a piece of the puzzle, given that it requires a valid excuse to cast an early ballot. But analysts have pointed out that turnout in heavily Democratic areas like Arlington County, Alexandria, Charlottesville, Richmond, Norfolk and Portsmouth is lower than elsewhere in the state. All were among Obama's top 10 best cities and counties.

There have also been dropoffs in the most Republican counties and cities from 2008, but not as big as in the places listed above.