The Democratic campaign has taken on the feel of “Groundhog Day,” repeating the same storyline over and over with only minor variation. Hillary Clinton, in our view, has spent most of the year in the liminal space between “clear favorite” and “presumptive nominee.” After barely beating Bernie Sanders in Iowa and badly losing to him in New Hampshire, Clinton reasserted herself in late February with a narrow win in Nevada and an overwhelming one in South Carolina, indications that (as we and a lot of other folks had originally expected) she would hold an advantage once the Democratic calendar turned to more diverse states.

Then, after a series of victories on Super Tuesday on March 1, Clinton emerged with a clear edge over Sanders, leading him by 187 pledged delegates. (Note that none of the numbers in this article account for superdelegates, who also favor Clinton.) Despite a shocking loss in Michigan on March 8, Clinton swept Ohio, Florida and three other states on March 15, expanding her lead over Sanders to 310 pledged delegates.

Sanders then ran off a string of victories, including his big win in the Wisconsin primary on April 5, to cut his disadvantage to 204 delegates. Still, because Sanders’s wins were coming on terrain demographically favorable to him — and because he had to gain delegates at a rapid pace to close his deficit with Clinton — he wasn’t necessarily doing all that much to improve his chances of winning the nomination. Then came an unambiguously bad result for Sanders last week in New York, when he lost by 16 percentage points.

Clinton’s current lead — 235 pledged delegates — is still below her post-Ohio peak. But because there are relatively few states left to vote, she now needs only 41.6 percent of the remaining pledged delegates to clinch a pledged delegate majority, her lowest figure of the campaign to date. Sanders, conversely, will need 58.4 percent of the remaining pledged delegates to win a majority.

That’s already a tall order for Sanders, but if polls and demographic projections are roughly correct in the five states set to vote today, Sanders’s math will become even more challenging, requiring him to win about 65 percent of pledged delegates in the remaining states to surpass Clinton.

Clinton has clear leads in our polling-based forecasts of Pennsylvania and Maryland, which together have 284 pledged delegates (more than New York’s 247). She also narrowly leads Sanders in our forecast of Connecticut, while trailing him by a percentage point or two in Rhode Island. We’re not running a forecast in Delaware since there’s been only one poll there, but Clinton led Sanders in that survey.

Polls are sometimes inaccurate in primaries. Michigan has been the only state in the Democratic campaign so far where the substantial majority of polls misidentified the winner, but it was such a huge miss that it needs to be kept in mind. Still, in this case, the polls don’t diverge much from what you might expect from the states based on their demographics. Furthermore, all of the states voting today except Rhode Island are holding closed primaries, another factor helping Clinton.

Below, you’ll find a polling-based and demographic-based forecast for each state, along with an allocation of pledged delegates on the assumption that they’ll be distributed in proportion to the statewide vote.

POLLING MODEL DEMOGRAPHIC MODEL STATE POP. VOTE CLINTON DEL. SANDERS DEL. POP. VOTE CLINTON DEL. SANDERS DEL. Pennsylvania Clinton +17 111 78 Clinton +13 107 82 Maryland Clinton +16 56 39 Clinton +31 62 33 Connecticut Clinton +4 29 26 Clinton +11 31 24 Rhode Island Sanders +1 12 12 Sanders +4 11 13 Delaware Clinton +7 11 10 Clinton +22 13 8 Total 219 165 224 160 Delegate gains are likely for Clinton on Tuesday

Clinton holds a 17 percentage point lead in our polling-based forecast of Pennsylvania. That would closely match her margins in neighboring Ohio and New York, although it seems a bit high according to the demographic model, which has Clinton winning Pennsylvania by a margin in the low teens instead.

However, Clinton’s 16-point lead in the Maryland polling forecast might be on the low side, partly as a result of a possibly dubious American Research Group poll showing a close race there. Other recent polls of Maryland showed Clinton with a 20+ percentage point edge, while our demographic model has her winning there by 31 points.

The demographic model also has Clinton winning Connecticut and Delaware by slightly more than the polls do, while it has Sanders as a bigger favorite in Rhode Island than the polls suggest. But these states have relatively few delegates and so deviations from the forecasts won’t matter all that much in either direction. Overall, the polling-based forecast shows 219 delegates to Clinton to 165 for Sanders, while the demographic forecast has a similar 224-160 split.

Suppose that the polling-based forecast is right and that Sanders adds 165 pledged delegates on Tuesday. He’d then need 653 of the 1016 pledged delegates in the remaining states, or 64.3 percent, to eventually reach a majority of 2,026 pledged delegates. Here’s an estimate of what that would require in each remaining state (these numbers are adapted from estimates that we originally built for Sanders last month).

DATE STATE OR TERRITORY NO. ELECTED DELEGATES SANDERS’S PATH-TO-2,026 PROJECTION POPULAR VOTE MARGIN NEEDED TO REACH TARGET May 3 Indiana 83 53 Sanders +28 May 7 Guam 7 4 Sanders +14 May 10 West Virginia 29 21 Sanders +45 May 17 Oregon 61 49 Sanders +61 Kentucky 55 36 Sanders +31 June 4 Virgin Islands 7 4 Sanders +14 June 5 Puerto Rico 60 36 Sanders +20 June 7 California 475 299 Sanders +26 New Jersey 126 73 Sanders +16 New Mexico 34 20 Sanders +18 Montana 21 18 Sanders +71 South Dakota 20 15 Sanders +50 North Dakota 18 15 Sanders +67 June 14 D.C. 20 10 Tie What Sanders’s path to 2,026 will look like if Tuesday polls are right

Based on these estimates, Sanders would need to beat Clinton by 26 percentage points in California, 28 points in Indiana and 16 points in New Jersey, all states where he trails Clinton in polling averages. He’d also need to win Western states like Oregon and Montana by 50 or more percentage points. No matter how much creative, mind-bending math they might be tempted to apply, Sanders and his campaign might have to “re-evaluate” his position in the race.

True, even an unexpectedly good day today wouldn’t help Sanders in the delegate count all that much. Suppose he splits pledged delegates with Clinton 192-192, perhaps as the result of upset wins in Pennsylvania and Connecticut. He’d still have to win 61.6 percent of the remaining pledged delegates to claim the majority.

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But candidates rarely end their campaigns after beating consensus expectations, even if their results aren’t all that impressive in an absolute sense (see also: John Kasich declaring victory after winning 16 percent of the vote in New Hampshire). And if Sanders doesn’t reconsider his campaign after Tuesday, there’s not a logical off-ramp for him before California on June 7; instead, the states set to vote in May look reasonably good for him. Clinton is extremely likely to be the Democratic nominee either way, but tonight could determine whether she continues to see Sanders’s shadow for another six weeks.

Check out our live coverage of the April 26 primary elections.