At this point in the race for the White House, there are some concessions that need to be made across the board. One, Hillary Clinton is set to be the Democratic nominee. Two, there is a formidable enemy and his name is Donald Trump.

In both Oregon and California, Sanders is trailing Clinton by at least 10 points, according to recent polling by multiple research groups. Without victories in these two states, a superdelegate turnover is out of the question and so is his presidency.

However, in protest, waves of Sanders supporters too massive for comfort have decided not to vote for Clinton, should she win the nomination. Instead, they plan on voting for Green Party candidate Jill Stein, writing in Sanders’ name on the ballot, or simply staying home. The movement, called “Bernie or Bust,” has been trending online since June of last year and has claimed a quarter to a third of Sanders’ nearly 10 million voters.

At the core of “Bernie or Bust” is the widespread skepticism of Clinton’s judgment for leftist policies, a thorn that’s been lodged in her side since the beginning of her campaign. Millions of voters say they cannot bring themselves to cast a ballot for a candidate they view as untrustworthy, with a foreign policy more hawkish and a history on trade more corporatist than the rest of her party.

Also drawing criticism on the trust factor, whether her supporters like it or not, Clinton is under investigation by the FBI about her private email server and faces the possibility (as small as it is) of indictment.

Sanders supporters see their champion, on the other hand, as a candidate who upholds the value of integrity and ideological consistency. The only problem is this champion will likely not be running in two months, and they will have to decide whether or not their attachment to an obsolete candidate is worth more than putting a Democrat in the White House and a liberal on the Supreme Court. It basically comes down to who’s more reliable: Hillary or a pro-torture sadist? Gee, that’s hard one.

Yet, this realization doesn’t seem to be sinking in. The Bernie or Bust idea is a frightening one to the establishment in this anti-establishment race. But it shouldn’t be worrisome just for party old-timers–it’s reason for anyone on the political left to fret. With House Speaker Paul Ryan and Trump “totally committed to working together,” there is more conversation among GOP officials about party unity than about a third party bid, meaning the final stretches of the race will not be getting any easier for the Democratic nominee, presumably Clinton.

Clinton and Trump are neck and neck in the most contested swing states—Florida, Ohio, and Pennsylvania— according to  a recent Quinnipiac general election poll. In both Florida and Pennsylvania, Clinton leads Trump with a single point, and trails him by four in Ohio. This is a no-brainer: Clinton needs to get all the votes she can in these battleground states and the way the numbers are now, there is little room to breathe. Any loss of base supporters spells asphyxiation.

For ardent Sanders supporters, what is offered as political pragmatism may very well resonate as plain defeatism. But take it from someone who just last month said Clinton was one person who should never come near the Oval Office. Sanders’ weak surge and likely defeat does not necessarily make Clinton more appealing as a candidate, but it’s time to get practical.

Sanders has already done his job in this election, and it wasn’t about claiming the nomination or the presidency. Sanders’ goal  was to inspire a generation of progressive voters to move America forward, doing away with corporate plagues killing the middle class. This was finished a long time ago. Now it’s on his voters to carry his momentum into the general election and into a Clinton presidency, which will be far from perfect.