In one of the greatest turnarounds in the history of presidential primaries, Joe Biden is now the undisputed leader of the Democratic nomination, with his main competitor, Bernie Sanders, having little chance of catching up on delegates.

The former vice president’s win in Michigan, called shortly after all polls closed, solidifies him as the presumptive nominee and demonstrates his ability to build a broad coalition of working-class, suburban, and minority voters in Midwest states once favorable to Sanders. The final margin of Biden’s victory has yet to be decided because of the high number of early ballots, but it was decisive enough for the race to be called by 9 p.m. Tuesday.