Primary elections

Wave watch: Inside the Democratic primary turnout surge

Data: Ballotpedia; Chart: Chris Canipe and Neal Rothschild/Axios

Democratic voter turnout in this year's House primaries increased in each of the 19 competitive, comparable House districts compared to 2014, and doubled in more than two thirds of them. That's far better than Republican voter turnout, which increased in 14 of those districts but didn't double in any of them.

Why it matters: Poor turnout has been the scourge of Democrats' efforts to win congressional elections in the last decade. But this data suggests that a surge of anti-Trump enthusiasm could boost their turnout in November — and not just in already-blue areas, but in parts of the country that could deliver control of the House to the Democrats.

New data: Democrats crushing Republicans in 2018 elections

Note: The 2018 data is preliminary through Sept. 12 and excludes runoffs, special elections and candidates who ran unopposed. Prior data includes unopposed candidates if they were on the ballot. Louisiana will hold their party primaries on Nov. 6 followed by a general election on Dec. 8; Data: Federal Election Commission (1998 to 2016) and Associated Press (2018); Chart: Chris Canipe/Axios

Riding a surge of enthusiasm in opposition to President Trump, more Democrats turned out in the primaries for House elections than Republicans this year — the first time that has happened since 2008.

Why it matters: 2008 was the last time Democrats won a majority in the House. They lost it in 2010, when Republican primary turnout skyrocketed and Democratic turnout plummeted — the reverse of what's happening now.

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