There is no way around it for Hillary Clinton supporters: last Saturday was a statistical massacre for the Clinton campaign. Sen. Bernie Sanders won all three Pacific caucuses—and he won big. It was difficult to watch CNN’s election coverage and not wonder whether John King’s magic wall was on the fritz.

Bernie’s romp through Alaska, Washington and Hawaii made his New Hampshire win look like a close contest. He swept Alaska by sixty-three points (81.6 to 18.4 percent), Washington by forty-five points (72.7 to 27.1 percent) and Hawaii by thirty-nine points (69.8 to 30 percent). Even more important was Sanders’s delegate tally at the end of the night. His victories earned him fifty-five delegates to Hillary Clinton’s thirty, allowing him to chip away at Clinton’s monumental delegate lead. If you were an alien looking down on Earth, you would reasonably assume that Democratic primary voters really dug the seventy-four-year-old grandpa from Vermont, frizzy white hair and all.

Talking to Sanders supporters in coffee shops and on the street, I get the overwhelming feeling that they truly believe last weekend’s blowout is the beginning of a new era in the 2016 Democratic presidential race. Bernie, of course, is more than happy to bask, telling NBC’s Chuck Todd that when he continues to win states as decisively, the superdelegates currently supporting Clinton will abandon her and carry him across the finish line to 2,383. “Our calculations are that in fact we can win the pledged delegates,” said Sanders. “And at a time when we have the momentum, we have won five out of the six last contests in landslide fashion, in all of the national polling that I have seen, we are beating Donald Trump by much greater margins than is Secretary Clinton.”

There is only one thing standing in the way of Bernie’s political revolution: reality. Sanders may feel that he has the wind at his back, but three particular obstacles will, more likely than not, prevent him from becoming the greatest primary spoiler in the history of contemporary U.S. politics.

1. Winner Takes . . . Some

Superdelegates notwithstanding, Clinton holds a 268 delegate lead as of March 28. If we were talking about the Republican primary, crawling back from a 268-delegate lead would certainly be achievable thanks to winner-take-all primaries. The Democratic primaries are a completely different story: delegates are awarded proportionally, which means the only way that Sanders can make up ground is by repeating the kind of overwhelming victories he achieved in Washington, Hawaii and Alaska. The chances of that happening are slim—only four big states, with delegate counts of at least 100, remain.

2. Superdelegates

Sanders supporters like to complain about the undemocratic nature of superdelegates, in which party officials and elected leaders get to vote for any candidate they want. The governor of New York, for instance, could decide to vote for Hillary Clinton even if Sanders wins the state (and vice versa). But this is how the Democratic primary system works, and complaining about it does nothing but make the Sanders campaign look petty.

Sanders supporters despise the superdelegate system because the vast majority allocated so far (94 percent) have pledged their loyalty to Clinton. And that makes the delegate math that much harder for Sanders. With 2,049 delegates left, Sanders would have to claim 67 percent in order to win the nomination. Put another way: Sanders would need to perform twice as well in the next three months than the previous two. Winning roughly 37 percent of the delegates, as he has so far, simply won’t cut it.

3. Unfavorable Demographics

It’s a well-worn cliché that Bernie does best in open primaries, where boatloads of independent voters can participate, and in caucus states with solidly white majorities. Clinton pummeled Sanders in the South because African American voters were simply not buying what he was selling. Clinton’s established inroads with minority communities have, to date, been among her strongest assets in the race.

With the exception of Michigan, Sanders has won in states where white progressives are the dominant participants. In Washington, where Sanders won big, the minority population is marginal (over 77.3 percent of the state is white according to 2010 U.S. census data). The same goes for Utah, another state where Sanders trounced Clinton in the primary (86.1 percent white).

These demographics will change as the calendar draws into the summer months. New York, Maryland, California, Pennsylvania, New Mexico and Delaware all have sizable African American or Latino populations—traditionally friendly turf for Hillary Clinton. Sanders has yet to break into these communities to the extent that one would expect of a Democratic nominee for president; besides winning the Latino vote in the Nevada caucuses, his track record with minority communities compared to Clinton has been beyond dismal. Do we really believe this trend will magically reverse before heading into the northeastern and mid-Atlantic states next month?

To put it crudely to Sanders supporters: your guy had a great showing this past weekend, but his landslide victories are an exception to the rule. As the Democratic nominating process returns to a more diverse electorate and as Clinton continues to accrue delegates (even if she loses), a wave of cold water will submerge the Cinderella story that is Bernie Sanders’s presidential campaign. And once that happens, it will be up to Sanders to convince his dedicated following of white progressives and young people to rally behind Clinton—that is, if Democrats hope to retain the White House for a third consecutive term.

Daniel R. DePetris is an analyst at Wikistrat, Inc., a geostrategic consulting firm and a freelance researcher. He has also written for CNN.com, Small Wars Journal and the Diplomat.

Image: Flickr/Gage Skidmore