The media called California for Bernie Sanders moments after the polls closed on Friday so everyone knows how that played out, right? Bernie Sanders won the Golden State, but not by as wide of a margin as earlier polls had predicted.

Well… maybe. The truth is that barely half of the votes have been counted. The “final” results we were given were largely based on exit polls and trends in the actual votes cast in person on Tuesday. But as The Guardian is reporting, there are more than five million ballots stacked up in bags at post office warehouses or on their way to officials to be tallied. And nobody knows how many of them were cast for which candidate because they were all mailed in early. One political analyst described it as a “black box.”

Bernie Sanders was declared the winner in California just moments after polls closed but his final haul of delegates could remain uncertain for days, or even weeks, as election officials tally the millions of provisional votes and mail-in ballots.

And while triumph in the Golden State will help Sanders remain competitive in what has become essentially a two-person race between him and Joe Biden, the eventual delegate math could indicate a decidedly shakier path to the nomination than the Vermont senator expected last week…

“It’s like there’s this black box of how many ballots are at the post office right now,” said [Paul Mitchell, of Political Data Inc.] So far, about 5.3m ballots have been counted, according to Mitchell, just over 50% of the 10m he expects have been cast in this election.

In a more normal election cycle, we wouldn’t expect any sort of huge shift in the projections because we’ve gotten fairly good at gauging such things based on exit polling. But this is far from a normal election cycle. Keep in mind that the California primary took place three days after South Carolina voted and barely 48 hours after two other candidates from the “moderate” lane who had measurable support dropped out.

We should also remember that California Democrats started voting 40 days before the actual primary date. At that point, Joe Biden’s campaign had been left for dead on the side of the road by many analysts (as Joe so loves to point out this week). Pete Buttigieg was being seen as an ascendent, competitive player after Iowa and New Hampshire. Bernie Sanders was being talked about as “inevitable” for a good portion of that period. And Michael Bloomberg was running a massive television ad campaign all over California in every major market. He was also rising in the polls.

With all of that in mind, how can we possibly know what story those five million ballots will tell? This is precisely the problem I was talking about yesterday when discussing the massive problems with extreme early voting. The bulk of those millions of ballots were cast by people who didn’t have anywhere near all the information they would surely have liked to have had when they sent them in.

For all we know, Bernie Sanders could have such a massive share of those ballots that he’ll take the lead back in the delegate count. Conversely, huge numbers of Californians may have been panicking over a potential Sanders nomination and voting in droves for Buttigieg. Or Biden. Or even Bloomberg. At this point, we’re trying to read the minds of people who were making decisions without a lot of information that voters had on primary day. It’s an exercise in futility. Yes, in all likelihood, Bernie Sanders won and will pick up a sizable pack of delegates. But there’s a non-zero probability that it might be much closer to a tie. Heck, he might have even finished second.