But not the only one facing Democrats this mid-winter of their malcontents. They have a fragile House majority to protect in the fall, and a Senate minority with a golden opportunity to take control of the upper chamber. If the top of the ballot pits a mainstream Democrat against Donald Trump, Democrats feel confident about their down-ballot chances.

If, however, the party nominates an old socialist crank as its standard-bearer, bye bye Beltway, say Democrats in both chambers. Roll Call talked with a few very anxious members in the House about their prospects, and found out that the damage is already being done:

Even before Sanders won the New Hampshire primary Tuesday, as expected, and came in a close second in the Iowa delegate tally to Pete Buttigieg, the former mayor of South Bend, Indiana, there were Democrats saying that nominating the senator from Vermont could threaten their House majority. They feared having the self-proclaimed democratic socialist at the top of the ticket could complicate efforts to win over the independents and moderate Republicans they need to win reelection.

“If it becomes a race between socialism and capitalism, yes, absolutely,” the majority is in danger, Minnesota Rep. Dean Phillips said. Phillips has endorsed his home-state senator, Amy Klobuchar, who finished third in New Hampshire.

Republicans were eager to tie vulnerable Democrats to Sanders. On Wednesday, the Congressional Leadership Fund, a super PAC aligned with House GOP leadership, highlighted a report from The Hill in which Reps. Elaine Luria of Virginia and Haley Stevens of Michigan said they would support the eventual nominee, Sanders included.

“Elaine Luria was never a moderate and her decision to pledge her support to a socialist for President should make that as clear as day,” CLF spokesman Calvin Moore said in a statement.

That puts Democrats in a vise. If they don’t say they’ll support the nominee regardless of who it is, then Sanders’ supporters will tear them to pieces, rhetorically speaking (at least), and they need the progressive activists to win their own elections. If they say they’ll support the nominee regardless, then they’re opening up the Overton window on socialism within the Democratic Party. And needless to say, socialism doesn’t sell anywhere else but there these days:

More than nine in 10 Americans say they would vote for a presidential candidate nominated by their party who happened to be black, Catholic, Hispanic, Jewish or a woman. Such willingness drops to eight in 10 for candidates who are evangelical Christians or are gays or lesbians. Between six and seven in 10 would vote for someone who is under 40 years of age, over 70, a Muslim or an atheist.

Just one group tested — socialists — receives majority opposition. Less than half of Americans, 45%, say they would vote for a socialist for president, while 53% say they would not.

That 53% opposition number may not be similar in every single House district, but it’s likely to be more the case in the districts Democrats won in 2018 to get their majority. If the Democratic Party becomes the Democratic Socialist Party — which will be the case in all but name with Sanders at the top of the ticket — then Democrats will find themselves once again marginalized to their urban cores and coastal enclaves, and Republicans might get their biggest House majority in a century.

That 53% opposition number is much more likely to be consistent state to state. That is why Senate Democrats are also clearing their throats about the danger Sanders represents:

Senate Democrats are feeling queasy about their party’s presidential primary after Sen. Bernie Sanders (I-Vt.) seized frontrunner status by winning the New Hampshire primary, while former Vice President Joe Biden stumbled to a fifth-place finish.

Democratic senators have been careful not to criticize Sanders publicly, fearing that it could undermine party unity heading into the November general election, which they view as a must-win contest.

But they have serious questions about the electability of their self-described Democratic Socialist colleague, and the problems he may create down ballot for vulnerable Senate candidates.

Republicans aren’t worried at all, The Hill reports, and maybe thinking it might help recruit a Democratic incumbent or two:

Republicans are rubbing their hands in anticipation of Sanders winning the Democratic nomination. …

Sen. Joe Manchin (D-W.Va.) told Politico Wednesday: “If Bernie ends up being one of these frontrunners, he’ll have to moderate. I’m not going socialist. Never been a socialist.”

So far, Sanders’ Senate colleagues are mainly keeping quiet about the nightmare scenario, but their anxiety is starting to get out into the open. If Sanders gets a significant haul of delegates on Super Tuesday, it may break out into open panic, collegiality be damned. Party loyalty doesn’t mean that they have to commit to professional seppuku, Sanders’ victimization fantasies notwithstanding. The game at that point will be to keep as many competitors viable as possible to force a brokered convention, and then organizing to lock Sanders out of the nomination.

It’s either that or watch the whole party burn to the ground, electorally speaking (at least) as a final refutation to the Democratic Socialists. That way they can at least start over with their hard-Left wing discredited and start listening to people outside their own bubble about what voters actually care about.