Bernie Sanders won caucuses over the weekend in Alaska, Hawaii, and the state of Washington. All three victories were by impressive margins of 70% or higher. With the clock ticking down, and Sanders still able to compete around the country, the looming prize on the Democratic side is the state of New York, which holds a primary on April 19th. It is the largest delegate prize in April.

Report from the Boston Globe:

In a mathematical squeeze to make up ground in the Democratic presidential race, Bernie Sanders is preparing for an aggressive push to defeat Hillary Clinton in New York at a time when the former secretary of state is trying to shift the focus to the general election.

The New York primary on April 19 looms as potentially determinative: A win by Clinton, who is favored, would further narrow Sanders’s path. A loss in the state she represented as a senator would embarrass her and hand Sanders a rationale to continue campaigning until the final votes are cast in June.

Clinton had enjoyed a lead of roughly 300 in pledged delegates, but Sanders narrowed the gap Saturday with solid victories in three Western caucuses.

In one of the most successful days of his campaign, the senator from Vermont easily won in Alaska, Hawaii, and Washington state. Sanders won a total of 55 delegates — 13 in Alaska, 17 in Hawaii, and 25 in Washington. Clinton picked up 20 — 3 in Alaska, 8 in Hawaii, and 9 in Washington.

After the Saturday voting, Clinton held a delegate lead of 1,243 to 975 over Sanders, according to an Associated Press analysis, an advantage that expands to 1,712 to 1,004 once the super delegates are included. It takes 2,383 delegates to win.

There is tentatively a Democratic debate slotted for April, though a specific date hasn’t been named. Bernie Sanders is pushing for a debate in New York prior to the upcoming primary, according to CBS News:

Bernie Sanders is challenging Democratic front-runner Hillary Clinton to schedule one more debate in April — this time, in her home state of New York.

“I would hope very much that as we go into New York state, Secretary Clinton’s home state, that we will have a debate — New York City, upstate, wherever — on the important issues facing New York and in fact the country,” Sanders said Sunday in an interview with NBC News.

Asked if he was worried Clinton would no longer want to debate him, Sanders responded: “Yeah, I do have a little bit of concern about that. But I certainly would like to see a debate in New York state.”

Sanders hopes to be competitive in the Democrats’ New York state primary, scheduled for April 19. The state has 247 delegates up for grabs and is the largest nominating contest in the month of April.

I’m not sure that Hillary will feel comfortable enough to avoid another debate, especially given that Sanders was able to sweep all three contests on Saturday with margins that must give the Clinton campaign some “heart-bern.”

Caucuses have been especially generous to Sanders, but he’s also pulled upset victories in big states like Michigan, which is what he’s counting on again in New York. That will, however, be a very tougher sell. The latest polling from New York gives Clinton a 34 point lead, which might be insurmountable.