Rep. Jeff Van Drew (D-N.J.) will reportedly switch parties this week over his decision to oppose impeaching President Trump. The move may have been unexpected, but the political pressures that drove him to jump are real and could cost the Democrats the U.S. House.

It’s been clear for a while that the House Democrats’ impeachment hearings have not moved public opinion toward impeachment. Quite the contrary: Opposition to removing Trump from office has risen in the past week. The RealClearPolitics polling average shows a plurality is opposed to impeaching and removing Trump from office, the first time that has happened since the details of his dealings with Ukrainian President Volodymyr Zelensky became public.

These facts make life extremely difficult for people such as Van Drew from swing districts. Polls show massive super-majorities of Democrats nationwide want the president impeached and removed. This means Democrats from swing districts face primary challenges if they don’t toe the party line. But they face defeat in the general election if they do, since polls also show that Republicans vehemently oppose impeachment. Democrats who represent normally Republican districts face a terrible Hobson’s choice.

The data suggests things are getting worse, not better, for Democrats who support impeachment. The RealClearPolitics polling average shows independents oppose removing Trump from office by six percentage points. This is a significant move in just a week. Five of the seven polls in the RCP average show opposition among independents rising since the last poll each organization conducted. Two show opposition rising by more than 10 points. The conclusion is inescapable: As the prospect of impeachment has solidified, opposition to impeachment increased among swing voters.

This is especially bad news because this comes at a time when the Democrats are controlling the narrative. The House Intelligence Committee hearings were essentially a brief for the prosecution, with witness after witness lined up to support the pro-impeachment narrative from Intelligence Committee Chair Adam B. Schiff (D-Calif.). The same was true in the House Judiciary Committee, as the number of witnesses stacked heavily in favor of pro-impeachment views. Imagine what could happen in the Senate when Majority Leader Mitch McConnell (R-Ky.) controls the rules.

That should greatly trouble the now-30 House Democrats who represent seats Trump carried in 2016. It’s easy to see that if removal is largely a passion of Democrats and Hillary Clinton backers, removal is opposed by pluralities or even majorities of voters overall in these seats. Sixteen of these members represent districts that Mitt Romney also carried in 2012, so these representatives have an even bigger uphill climb.

But the 14 who sit in “Obama-Trump” seats may have just as large a challenge. Voters there have personal allegiance to Trump, and in many cases Trump received a larger share of the vote than in the more historically GOP seats. Seven of these members are in their first terms and are thus not yet entrenched in their seats. Republicans are already spending millions of dollars in ads tying these members to the unpopular impeachment inquiry. Expect that barrage to continue throughout the next year.

Van Drew may not win his Republican primary. None of the three Republicans who were already running against him say they are backing out, and local party officials have been non-committal about whether they plan to back the former Democrat. But he was a certain goner in a Democratic primary as Democrats essentially abandoned him after he voted against the impeachment inquiry. Jumping ship mid-voyage could leave Van Drew sunk in the water, but he apparently believes that gives him better odds than being told to walk the plank.

Almost all House Democrats in swing seats will back impeachment on Wednesday. This will let them live to fight another day, but in the face of a certain Senate acquittal, their vote looks mainly like a futile gesture meant to forestall the progressive mobs. We’ll see how many survive a full trial by their peers next November.

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