How does early voting help political parties?

As you can imagine, over the past few days we’ve fielded a vast (for our small staff) number of questions about early voting, its history, and so on. One of the questions that comes up repeatedly is: how does early voting help political parties?

On the face of it, it’s a reasonable question. Paul Gronke likes to talk about the voting electorate as an apple pie. If you remove a slice of early voters, then there are that many fewer voters on Election Day. If there’s a certain slice of the electorate that is going to vote—and early voters do tend to be more committed partisans—why would the parties care when they did so?

Indeed, there are many reasons why campaigns might dislike early voting. It forces them to run a longer, more sustained endgame. Days like the Friday and Monday before Election Day become major events in their own right, requiring sustained advertising spend. Studies have not found clear turnout increases from early voting systems. And, indeed, wide dissemination of the results might induce complacency for leaders in the early vote (I suspect this is going to garner much attention in the post-election discussion). If nothing else, the old system was familiar: elected officials can reasonably be expected to be suspicious of change to a system they know well.

The first question also prompts a corollary: why have election commentators made so much of the high Democratic turnout? If Democrats are particularly enthused and excited by this election, then they might well be expected to get out and cast their votes as soon as possible. But these voters were going to turn out anyway, presumably. What does early voting add to this equation?

In part, the answer lies in targeted canvassing. Most of the states provide—with varying levels of restriction—detailed breakdowns of early voters. And I don’t mean just broad partisan or demographic trends, but individual-level voter information (typically at least name and address). If the data aren’t contained within the returns themselves, a list of voter identification numbers usually is, and this list can be compared to voter registers to obtain detailed information. North Carolina—a state we’ve been following closely—makes such data freely available on its website. Florida, too, provides extensive information about early in-person voters (though absentee data are restricted by law to registered parties).

For candidates, this is a dream come true; it turns out that one ‘in the bank’ is more valuable than it would initially seem. By turning out committed partisans early, campaigns can check them off, and then focus their get-out-the-vote efforts in the last few days on marginal and undecided voters. Campaigns have a vast machinery in place on the ground in many states, but their resources and time are still limited. Early voting allows them, essentially, to stop wasting precious time on those who have voted.

This aspect of early voting is crucial to understanding why the results so far give Barack Obama’s campaign a significant advantage. It’s not necessarily because we think the partisan ratios are a harbinger of things to come. Certainly, we don’t anticipate a 70%-30% victory (or insert your favorite exuberant prediction here). This is not Election Day writ-large, and it would be quite dangerous to make forecasts from early voting returns. That said, a large chunk of the Democratic base has now turned out in swing states like Nevada, Florida, and North Carolina—and the same cannot be said for Republicans. While the McCain campaign will be forced to spend a large part of the last few days ensuring that its base turns out in sufficient numbers, the Obama team will be able to focus its efforts on persuading and turning out valuable swing voters.

I should be clear: we’re a non-partisan academic research center, and we try to study and present all interesting aspects of early voting, regardless of the party angle. All the same, it’s very hard to spin the numbers we are seeing so far in any way that doesn’t tell a bad story for John McCain.