Today’s the big day: it’s Election Day in the U.S. This is the day we all go out and select our president.

Sort of. The first Tuesday in November is set as the official day to go to the polls. But many states now allow early voting and/or place few restrictions on absentee voting. ThinkProgress created a map illustrating the availability of early voting:

In Nevada, early voting began October 20th. All registered voters receive a schedule of early voting locations; some are open every day, while additional locations open on weekends.

I voted at a grocery store on the afternoon of the 20th. I was surprised there was a line. A poll worker said they expected more than a thousand people would vote in that location on that day alone, up from about 800 the first day of voting in 2008.

The appeal of early voting is pretty obvious: more time to do it, a greater likelihood that you can vote without having to take off of work, spreading voting out over time means shorter lines and less waiting to cast your vote, convenient locations, and also when a pollster calls and you tell them you already voted, sometimes you get to skip a lot of their questions.

So how many people take advantage of early voting? The Pew Research Center released some data about the 2008 election. A third of voters said they voted early, either in person or by mail:

That’s a third of all voters — but a number of states, especially on the East Coast, don’t offer early voting. In the South, 42% of voters had cast their ballots before Election Day, according to the full report.

Early voting is expected to be more common this year than in 2008. For instance, 56% of all registered voters in Nevada, one of the coveted swing states, went to the polls before early voting ended on Saturday. That will likely be 65-70% of the total turnout.

Voters’ behavior indicates a clear preference for early voting. It can address at least some of the reasons given by those who are registered but do not vote as obstacles to their participation, especially if voting by mail is an option.

We still focus on Election Day as the day, because it’s the end of the election cycle and, for many voters, still their only option for voting (and we may see a shift back in this direction, as states like Florida have restricted early voting). But in some of the all-important swing states that make or break a candidate’s bid for the presidency, the outcome of the election has already been decided; Election Day just determines the margin of victory.

Gwen Sharp is an associate professor of sociology at Nevada State College. You can follow her on Twitter at @gwensharpnv.