It is a message Democrats will be sending in suburban precincts all over the United States during the 2016 campaign’s final days: Defeating Donald Trump isn’t enough. Fully rejecting Trumpism also means routing Republican House and Senate candidates who showed any ambivalence in pushing back against a nominee that so many upscale voters regard with horror.

Rudra Kapila, a Democratic organizer, explained the mission to a group of volunteers who filled a cheerful suburban home here just outside of Washington on Tuesday night to work a party phone bank. “The idea,” she said, “is to get folks to vote Democrat down the ballot.”

It’s an objective that really matters in Virginia’s 10th Congressional District, where Republican incumbent Barbara Comstock faces Democrat LuAnn Bennett in one of the most closely contested House races in the country. If Democrats are to have any chance of gaining the 30 seats they need to take over the House — a long shot still — they have to win in places like this, where Hillary Clinton is expected to enjoy large margins.

Comstock, a staunch conservative and longtime Clinton critic, is well aware that Trump is poison for many of her constituents. She supported Marco Rubio in the Republican primary and criticized Trump along the way. When the “Access Hollywood” video of Trump’s crude descriptions of sexual assault was released, Comstock described it as “disgusting, vile and disqualifying.” She said she couldn’t vote for him and urged him to withdraw.

The list of Republicans who reject their presidential nominee, Donald Trump, and support his Democratic opponent keeps growing. (The Washington Post)

But for Bennett, it took Comstock far too long to get to that point. “My question to her is: Where have you been? Why now and not before?” Bennett said in an interview after she greeted the volunteers. “She has been one of the many, many enablers of Donald Trump. She spent most of this presidential campaign dancing on the head of a pin.”

Many vulnerable suburban Republican candidates have waltzed around Trump because they need votes both from his supporters and also from independents and Republicans who loathe him. Kelly Ward, the executive director of the Democratic Congressional Campaign Committee, said the uncertain trumpets sounded by so many GOP candidates are hurting them twice over: They look unprincipled to anti-Trump voters and disloyal to Trump’s ardent backers. In some House districts, Republicans are getting mailers reminding them of the inconstancy of their party’s candidate.

However the results come in, these congressional elections represent a sea change in how the two parties view their opportunities. Many of the more rural and working-class districts that were friendly to Democrats when the party took back the House in 2006 are now reliably Republican. Democrats have moved their hopes up the class scale and further into the suburbs.

I asked my researchers Adam Waters and Mohamad Batal to help compare the 31 seats Democrats picked up when they regained the majority in 2006 with the 38 seats the Cook Political Report defines as most competitive this year. The 2006 districts were, on average, 29.2 percent rural; the 2016 targets only 19.3 percent. Adjusting for inflation, the 2016 seats had an average median income $5,157 higher than the 2006 districts had. And bear in mind, some parts of the country suffered income decline in that period.

By making even more highly educated, metropolitan and ethnically heterogeneous seats competitive, Trump is speeding up a political transition that was already underway. It will be a problem for Republicans in the longer run, even if they hang on to the House this year, as a more diverse electorate and a new generation that is primarily moderate or progressive comes to predominate in more districts.

The Trump effect has already improved the Democrats’ chances of taking the Senate. In the House, they are now on track to add about a dozen seats, and pickups in the high teens or low 20s are quite possible.

But because of district lines drawn mostly by Republicans and the clustering of younger and minority voters in big metropolitan areas, picking up the 30 House seats Democrats need to take control remains a reach. They will have to be bolstered by a high level of participation from their partisans, an abandonment of the bottom of the GOP ticket by some share of anti-establishment Trump voters, and a Trump-induced slide in Republican turnout.

Virginia’s Bennett sees Trump creating a “lose-lose” situation for her opponent. That’s why she and scores of other Democrats will not let voters forget the name that sits, like a very heavy weight, at the top of the Republican ticket.

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