The primaries of April 26th––Maryland, Pennsylvania, Delaware, Connecticut, and Rhode Island––saw both parties’ front runners broaden their leads. Donald Trump won a clean sweep, earning nearly 60% of the vote in each state. Hillary Clinton performed similarly, beating out Bernie Sanders in 4 out of the 5 contests, the exception being the state of Rhode Island.

It was a grim night for Ted Cruz and John Kasich, the two trailing Republican candidates, who each failed to pick up the delegates they needed. At this point, both Cruz and Kasich are mathematically eliminated from the race. The only thing keeping them from dropping out is their alliance, which they formed in the aim of stopping Trump. Last night’s landslide, however, may have put an end to their plan. Trump’s victories on Tuesday night garnered him nearly all of the delegates at stake, putting Cruz and Kasich even further behind than expected.

Sanders finds himself in a similar position––by most statisticians’ estimates, it is now nearly impossible for him to clinch the Democratic nomination.

So why haven’t these losing candidates dropped out yet?

Sanders has pledged since the beginning to stay in until the end, but dropped a hint in his latest campaign email that the next contests will be issue-oriented. Or, in other words, he will be laying off the Hillary attacks, and preparing to help her in the general election.

Cruz and Kasich are different. Cruz insists that the campaign is “far from over,” while Kasich has stayed quiet.

Despite the assurances of these politicians, it seems almost certain that November’s election will be between Trump and Clinton––a prospect that frightens many, from far-left Sanders supporters to neoconservative Republican establishment figures.