With her announcement that Democrats will move forward and vote on articles of impeachment, House Speaker Nancy Pelosi, D-Calif., may have signed a political death warrant for dozens of moderate Democrats elected in Trump districts.

Pelosi is speaker today because in 2018 Democrats were able to convince voters in 31 House districts Trump carried two years before to defect and vote for them. Democrats need these voters to stay in their column in 2020 if they are to hold onto the House and win back the White House.

But in key swing states, large majorities of these 2018 defectors now say they plan to back Trump again in 2020. The New York Times reported that “nearly two-thirds of voters in six battleground states who voted for President Trump in 2016 — but for Democratic congressional candidates in 2018 — say they intend to back the president against each of his top rivals.” The Times also reported that in 2018, voters in these states cast their ballots “for Democratic congressional candidates by an average of six points, all but identical to their actual winning margins.” That means these freshman Democrats already face an uphill battle to hold onto their seats.

Now, Pelosi is adding to their woes by forcing them to vote to recommend the removal of a president that voters in their districts say they plan to reelect. Already, she forced them to vote to authorize an impeachment inquiry, and all but two did so. But there is a world of difference between backing an impeachment inquiry and voting to impeach. Before the hearings began, swing-state voters said they supported the impeachment inquiry by a margin of 50% to 45%, but opposed impeaching and removing Trump by 53% to 43%. After weeks of wall-to-wall hearings, polls show that Democrats failed to move the needle in favor of impeachment and removal. Indeed, in Wisconsin, opposition to removal has nearly doubled. In other words, Democrats have failed to make their case.

By moving forward with impeachment anyway, Pelosi is putting her most vulnerable members in a terrible position. Split-ticket voting is already rare. The Washington Post reported in 2016 that that election “saw the highest percentage of STRAIGHT-ticket voters in more than a century.” And according to FiveThirtyEight, split-ticket voting hit a new low in 2018. Impeachment makes it even less likely that swing-state voters will split their tickets. Are voters really going cast ballots to give Trump four more years and also to reelect the Democratic House members who tried to take that decision out of their hands by impeaching him?

Voters in these Trump districts are already frustrated with their Democratic representatives. They won on promises to work with the president to address issues like health care, prescription drug prices, infrastructure and trade. None of that is getting done, thanks to Democrats’ focus on impeachment. Indeed, there is speculation in the White House that the reason Pelosi has been slow-rolling the U.S.-Mexico-Canada free trade agreement Trump negotiated is not out of reluctance to give Trump a win, but because she needs it as leverage with her moderate members to get their votes for impeachment. “She’s using USMCA to get the impeachment vote,” Trump has said.

Pelosi isn’t stupid. She would not have announced a vote on articles of impeachment if she didn’t believe she had the votes. But while she can strong-arm the moderates in her caucus, she can’t strong-arm the voters in their districts. Her decision to move forward with impeachment means that many of those 31 Democrats seem destined to lose in November. Apparently, that is a price she is willing to pay to placate her party’s virulent anti-Trump base.