In an act of what residents of former New York mayor Mike Bloomberg’s hometown might refer to as “chutzpah,” an adviser to Bloomberg’s presidential campaign this week suggested that lower-polling candidates in the Democratic presidential nominating contest should drop out — including candidates who, unlike Bloomberg, have already won delegates and votes.

The rationale behind the request was simple. With Sen. Bernie Sanders (I-Vt.) poised to capture a large number of delegates on March 3 — Super Tuesday, when about a third of all of the delegates at stake will be awarded — time might be short for any other candidate to actually catch Sanders. If Sanders is running against four or five other candidates, all of whom have some support, it’s much easier for him to build up a delegate lead.

There are a lot of factors at play here, including the two counterbalanced rules the Democratic Party uses to allocate delegates. In any state, the delegates at stake are distributed roughly proportionately, meaning that better-performing candidates get more delegates. That’s different than many Republican Party primary contests, in which the winner of a state gets all the delegates. In order to win any delegates, though, the Democrats need to clear a 15 percent threshold of support. Get 14.9 percent of the vote in a primary and you get zero delegates — as many as if you had dropped out in the first place. Which is sort of the point raised by the Bloomberg campaign: If your candidate is polling at 10 percent, why stick around to earn no delegates?

Those rules were clearly not designed for a situation like the one in which the party finds itself. Setting aside the self-serving argument by Bloomberg’s camp, the party is in fact headed toward a bizarre scenario. It could wind up with a clear front-runner in the delegate count — who is nonetheless unable to clinch a majority of the delegates, and therefore the nomination, before the party’s convention.

At the moment, Sanders isn’t leading the field. Thanks to the above rules, he is slightly behind former South Bend, Ind., mayor Pete Buttigieg with 21 delegates to Buttigieg’s 23. The first two contests that have been held, in Iowa and New Hampshire, award relatively few delegates, so each major candidate still in the race essentially needs to win just over half of the remaining delegates to clinch the nomination. Nothing too shocking here.

What the Bloomberg adviser was reacting to, however, were projections from FiveThirtyEight indicating that after Super Tuesday, Sanders would have a large delegate lead. Why? Consider California. There, Sanders’s lead across the state should be enough to lock up about 193 delegates of the 415 at stake, according to FiveThirtyEight’s projections. In other words — nine times as many delegates as he currently has. The rest of the delegates in the state will be splintered among four other candidates, allowing the Vermont senator to increase his lead.

By the end of Super Tuesday, FiveThirtyEight estimates that Sanders will have earned about 4 out of 10 delegates that will have been awarded.

But remember: To clinch the nomination, candidates need to earn a bit more than 50 percent of the delegates awarded after New Hampshire. While Sanders is projected to have a lead, the percentage of the rest of the delegates he needs to win will have gotten bigger. Right now he needs to win 50.3 percent of the remaining delegates. If he does as well as projected on Super Tuesday, he will have won only a bit over 40 percent of the delegates to that point, well off the 50-percent-plus pace. After Super Tuesday, then, he will need to win more than 56 percent of the remaining delegates, in part because there are far fewer delegates remaining.

That’s harder than it sounds, since delegates are awarded proportionately. Even if the field narrows to three candidates after Super Tuesday, those candidates will likely consolidate some support — and, therefore, will be more likely to hit the 15 percent threshold to earn delegates. If Sanders is at 55 percent in national polling after the field narrows and earns that percentage of delegates in each contest moving forward, he will not have enough delegates at the end of voting to clinch the nomination.

That said, he also probably cannot be caught. If FiveThirtyEight’s projections are right, the next-closest candidates will be Bloomberg and former vice president Joe Biden, each of whom will have about 270 delegates to Sanders’s 608. In other words, they need to close a 330-delegate gap.

In contests that award delegates proportionately. Meaning that they can’t just win big states, they need to win big states by wide margins, so that Sanders gets fewer delegates. In order to surpass Sanders, Biden and Bloomberg need to win about 57 percent of the post-Super Tuesday delegates, thereby ensuring that they’ve earned at least 14 percent more delegates than the senator out of those remaining. (The math, quickly: 14 percent of the 2,467 delegates in play after Super Tuesday is about 345 delegates.)

For candidates who are further behind, that hill is steeper.

It’s not impossible that Sanders could consolidate enough support to clinch the nomination, nor is it impossible that he can be caught. I mean, obviously; only two states have voted. But these twin factors — the 15 percent threshold and the proportional distribution of delegates — make it harder for him to clinch and harder for him not to enter the convention with the most pledged delegates if FiveThirtyEight’s projections are right.

This is something Sanders knows well. In 2016, he trailed Hillary Clinton in the delegate math by a wide enough margin that he couldn’t catch her as the primaries continued. That year, he hoped to convince delegates at the convention that he deserved the nomination anyway. This year, we can assume, his arguments might be different.

Last week, we made an interactive tool allowing you to see how tricky it might be for a candidate to clinch the nomination. We’ve update it, below, to include FiveThirtyEight’s delegate projections. Play with the percentages for each candidate to see how hard (or easy) it might be for each to win the nomination. Or just click the “next” button using current national polling to see how hard it would be to catch Sanders — or for him to clinch.

Biden
Bloomberg
Buttigieg
Klobuchar
Sanders
Steyer
Warren
Other

March 3

Super Tuesday

1,512 delegates | 2,467 remaining

CandidateDelegatesAddedNeeded
Biden 270
0 1,721 69.8%
Bloomberg 273
0 1,718 69.6
Buttigieg 157
0 1,834 74.3
Klobuchar 55
0 1,936 78.5
Sanders 608
0 1,383 56.1
Steyer 22
0 1,969 79.8
Warren 127
0 1,864 75.6

That, in a nutshell, is the Democrats’ problem.