Bernie Sanders won a trifecta of states on Saturday. He put up big victories in Alaska, Hawaii and Washington, after carrying Idaho and Utah earlier in the week. Sanders beat his delegate targets by a solid margin in all five of these states and closed Hillary Clinton’s pledged delegate lead to just north of 225. In doing so, Sanders highlighted an ongoing Clinton weakness: caucuses. All five of Sanders’s wins this week came in caucuses. The problem for the Sanders campaign is that there are only two caucuses left on the Democratic primary calendar.

Here are the FiveThirtyEight delegate targets for every state to vote so far, as well as how many delegates Sanders won:

SANDERS’S DELEGATES STATE CAUCUS WON TARGET DIFFERENCE Washington* ✓ 74 59 +15 Utah ✓ 27 19 +8 Illinois 78 71 +7 Kansas ✓ 24 19 +5 Idaho ✓ 18 14 +4 Alaska ✓ 13 9 +4 Hawaii ✓ 17 13 +4 Colorado ✓ 38 36 +2 Vermont 16 14 +2 Oklahoma 21 20 +1 Maine ✓ 16 15 +1 New Hampshire 15 15 — Missouri 35 35 — Nebraska ✓ 15 15 — Michigan 67 67 — Minnesota ✓ 46 47 -1 Nevada ✓ 15 18 -3 North Carolina 47 50 -3 Arkansas 10 14 -4 Louisiana 14 18 -4 Iowa ✓ 21 26 -5 Massachusetts 45 50 -5 South Carolina 14 21 -7 Georgia 29 37 -8 Alabama 9 18 -9 Mississippi 4 13 -9 Virginia 33 43 -10 Ohio 62 72 -10 Arizona 31 41 -10 Tennessee 23 34 -11 Texas 74 96 -22 Florida 73 98 -25 Sanders outperforms expectations in caucuses *Washington’s delegate total won by Sanders is preliminary

Sanders has outperformed his targets in 11 states. Just three of those states held primaries (Illinois, Oklahoma and Vermont), and one of those three (Vermont) is Sanders’s home state. The other eight were caucuses. Six of Sanders’s best states by this measure were in the West (all the caucuses this week and Colorado). In fact, Iowa and Nevada are the only caucuses so far in which Clinton beat our delegate targets by more than one delegate, which may have something to do with all the organizing effort the Clinton campaign put into those states.

So why is Sanders doing better in caucuses than primaries? The most obvious answer is that caucuses reward candidates with diehard supporters. There are often speeches, and sometimes multiple rounds of voting at caucuses. Typically, you have to stick around for a while to vote. That takes devotion, and if you’ve ever met a Sanders fan, you’ll know that many would climb over hot coals to vote for him.

Sanders’s strength in caucuses may also be, in part, coincidental. Every state that has held or will hold a Democratic caucus this year has a black population at or below 10 percent of the state’s total population, and black voters have been among Clinton’s strongest demographic groups. Without those black voters, Clinton just can’t match the enthusiasm of Sanders’s backers. (In Southern states, where Clinton romped, her voters were far more enthusiastic than Sanders’s supporters were.)

Now, I know what some of you are thinking: How do we know that Sanders’s big wins this week aren’t a sign that something more fundamental about the Democratic race has changed? We don’t, necessarily. But look at the calendar: Sanders also outperformed his delegate targets in Colorado, Kansas and Maine earlier this month, and he still went on to suffer big losses on March 15. And that was after his shocking Michigan victory. Moreover, Sanders greatly underperformed his delegate targets last Tuesday in Arizona, which held a primary and has a more diverse electorate.

Most likely, Sanders will need to find another way to make up ground on Clinton in the delegate race. Wyoming (April 9) and North Dakota (June 7) are the only remaining stateside caucuses. The rest of the stateside races are primaries. Sanders has exceeded his delegate targets in just three stateside primaries. He’s matched them in three and underperformed in 15. Given that Sanders is still so far behind in the delegate count, he needs to outperform his delegate targets by a lot.

How likely is that? Well, he’s behind by about 6 percentage points in Wisconsin, according to FiveThirtyEight’s weighted polling average. That’s not a huge deficit, and it wouldn’t shock me if Sanders won Wisconsin given that the black population there is below 10 percent. (To match his delegate target in Wisconsin, he needs a net gain of 10 delegates there.) Sanders, though, will likely have more difficulty in later primaries in April, such as Connecticut, Delaware, Maryland, New York and Pennsylvania, where African Americans make up more than 10 percent of the state’s population.

Sanders had a strong week, and this has been a crazy year in politics. But there’s nothing in the recent results to suggest that the overall trajectory of the Democratic race has changed. Clinton was and is a prohibitive favorite to win the nomination.

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