FLORIDA: Democrats Lead In Early Voting Tally

The Washington Post argues that early voting tallies are highly predictive:

Early voting is underway in many states, and things seem to look good for Democrats. CNN suggests that Democrats have improved their standing in Arizona and Nevada, compared with 2012. Democrats also are voting at high rates in the key battlegrounds of Florida and North Carolina, according to news reports. The New York Times is estimating the November vote in North Carolina, using the early vote totals and other information. That model predicts a Hillary Clinton victory.

Since people’s actual votes are secret, these predictions are generally based on the number of registered Democrats and Republicans who have voted early. But how well does the early vote actually predict election outcomes? Political scientist Seth Masket at FiveThirtyEight, who analyzed 2012 early vote data, argues that it isn’t a good predictor of the eventual outcome in a state. But using a different set of data, we find that early vote numbers tell us a lot about which candidate will win.

Data collected by the voter firm Catalist and the Atlas Project show the number of early and absentee ballots cast in the run-up to Election Day in 2008 and 2012 for every state where the early vote amounted to at least 10 percent of the eventual total vote. By comparing the share of early votes cast by registered Democrats and Republicans to the final vote in those states, we can determine how well early voting predicted Barack Obama’s vote share when he ran against John McCain (in 2008) and Mitt Romney (in 2012). This calculation sets aside unaffiliated voters or those registered with a third party.

Hit the link for their graphs.