Yes and no. It's a two-party system and a lot of people vote for candidate X to stop candidate Y getting in. Indeed IIRC a lot of democrat messaging around the previous election was explicitly about stopping Trump rather than the merits of whoever their guy was.
Enough people did not vote against Trump is my point. "The democrats" voted against Trump, otherwise they don't really count as part of "the democrats" for this election, right?