(CNN) Early voting is a tricky indicator for predicting elections, since it's hard to know whether voters who cast ballots early would have voted anyway on Election Day but are simply doing it sooner -- or if they represent new voters altogether.

But one thing is clear: the share of younger people voting early in Texas and Georgia is far outpacing anything seen at this point during the last midterm election, in 2014. The trend holds for both those voters aged 18-30 and those 30-50.

And while the share of younger voters has gone up so far, the percentage of seniors over 65 voting early, even though they are still the largest single bloc of early voters in either state, their overall share has fallen sharply. The group between the ages of 50 and 64 stayed virtually the same.

Both states are the scene of closely watched races: in the Texas US Senate race, Rep. Beto O'Rourke is trying to unseat Republican Sen. Ted Cruz, while in Georgia Democrat Stacey Abrams and Republican Brian Kemp are vying to become the state's next governor in a contest that's largely mirrored the national political climate.

If these early voting numbers actually do turn out to be a harbinger of increased turnout among younger voters, that could be great news for Democrats. According to a Harvard Institute of Politics poll released earlier this week, voters under 30 are much more likely to say they'll vote now than they were in 2014, and they are a deeply Democratic-leaning group.

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