Democrats need roughly two dozen pick-ups in November to win the U.S. House of Representatives. I say “roughly” because it’s rare that a party loses no seats (Democrats lost a New Orleans seat in 2008, but picked it back up in 2010, for example). There is much argument about how they should do that, and what voters to target. To answer those questions, geography helps.
There are not many seats to win in “blue” areas. There’s a seat in New York City, maybe two if you count nearby suburbs. There’s not much to grab in Los Angeles. Chicago is basically solid blue in the city area. Philadelphia has one seat in the city. Atlanta, Miami, Detroit, San Francisco, and any other big city you add in doesn’t offer a combination of seats large enough to get two dozen seats. You basically can’t get to a majority using safely Democratic seats and voters. They’re not distributed broadly enough to do that. While I believe the base of any Presidential victory in 2020 for Democrats begins with the Obama/Clinton coalition of votes, that’s not going to win back the House for Democrats any time soon.
This means that the road to a functioning Democratic House Majority is essentially running through suburban America. That means nominating moderate candidates. When Democrats last won the U.S. House in 2006 and 2008, they were winning with candidates like Jason Altmire in suburban Pittsburgh. Was Altmire something to excite liberal activists? No, it’s fair to say not. He lost an incumbent on incumbent primary in 2012, so I don’t think he was “loved” by activist Democrats. Who did love him though? Suburban Pittsburgh general election voters who elected him three times. It’s worth repeating again though- we had a majority for two-thirds of his tenure. Those were actually the “good ole’ days.” When Blue Dogs existed, and so did a Democratic Speaker.
The “big, blue wave” of 2016 is not going to look much like the current Democratic Caucus in the House, if it happens at all (I’m not totally convinced the Biblical wave is on it’s way). It’s also not going to look like a Bernie Sanders rally. The new members of a Democratic Majority won’t pass all the litmus tests, won’t be good at purity, and might have very different rhetoric than the current members. The may even (*gasp*) be open to compromises on policy with a potentially narrowly divided Senate and Republican White House.
I guess what I’m saying is “the big, blue wave” of 2018 might be purple. Purple is better than red though.