There was a lot of attention paid to the fact that Republicans in Florida were pushing voters to cast absentee ballots. But it seems that this is a much more widespread phenomenon, and that both parties are urging supporters to lock in their vote in a number of states where it is legal to vote early by absentee ballot. From Nathan Newman (emphasis added):

At least a dozen battleground states allow voters to cast ballots early, including Florida, West Virginia, Nevada, Arizona and Iowa.

Both liberal and conservative groups are already mobilizing to get those ballots turned in as early as possible as part of their GOTV operations. Estimates are that up to one third of ballots will already have been cast by November 2.

The original Wall Street Journal article points out that this could create a number of problems, including the potential to pressure people into public voting:

each step in the process — an individual voter’s request for an absentee ballot, the elections official’s mailing of the ballot and the voter’s return of that ballot — becomes a matter of public record. During the early voting period, campaigns can communicate specifically with voters who have received ballots but haven’t yet voted. “ACT is going to know exactly what’s happening” with its target universe, says Mr. Link, the Iowa director.

While the WSJ focuses on liberal groups such as ACT, I think this really is a cause for concern no matter which side you are on. Not to mention the way in which early election results will affect the November vote.