Bernie Sanders has won Minnesota's Democratic caucuses, according to multiple media reports.

Sanders definitely needed a win in Minnesota to keep his campaign alive, and he was expected to pull it off. The state's heavily white, liberal Democratic electorate is very similar to the states where Sanders has been strongest: Iowa and New Hampshire. And Minnesota was one of the states the Sanders campaign focused its energies on in the days leading up to Super Tuesday.

What does this mean for the Democratic race?

The real measure of how important Minnesota is to the broader Democratic primary battle is whether it makes it more or less likely that Sanders will be able to catch up to Hillary Clinton's support. Because the primary calendar is spread out, it's totally plausible that Clinton could come out to an early lead as her stronger states vote early — then watch it evaporate as pro-Sanders states turned out to the polls later. (Or vice versa.)

One way to figure out if Clinton's lead is temporary, or if Sanders is running out of time to close the gap, is to work backward. If Sanders and Clinton had exactly equal amounts of support among all Democratic primary voters in America, what would the race look like right now? What would have happened in Iowa, New Hampshire, Nevada, and South Carolina, and what would happen in the Super Tuesday states tonight?

Nate Silver and the team at FiveThirtyEight have one way of estimating that. They use the demographics of each state to predict how much that state would "lean" toward Clinton or Sanders if the race were tied nationally.

According to that model, if Sanders were tied with Clinton nationally, he'd be beating her by 21 points in Minnesota.

This is the story of the night for Sanders — he's winning the states he needs to win (except Massachusetts). The question is whether he's winning them by enough. Generally he's been doing worse in individual states than he would do if he were tied with Clinton nationally. To know what Minnesota actually means for the future of the Sanders campaign, we'll need to know more than just who won.