It didn't really. Sanders lost the nomination and a large chunk of his supporters are supporting Clinton now as the "less bad" option.

Through the magic of money and super PACs

http://www.thedailybeast.com/articles/2016/04/21/hillary-pac...

As the election approaches, many more ordinary people start paying attention to politics. In the year before an election, political forums are filled with die-hard supporters of candidates that inspire the most passion; now, the vast contingent of people who prefer Hillary have entered the discussion.

It just means that the sub is more "anti-trump" than "pro-clinton" right now, even though the end result in both cases is similar.

It's not hard to understand at all. Dominating the voting in the new-queue takes a lot of effort. When Bernie was in the race such efforts had a potential pay off. Now that Bernie is gone there's no longer any reward. The reward has now shifted to getting Clinton elected and/or keeping Trump from being elected. Incentives drive behavior.

Hillary is spending 6mm+ on Internet astroturfing.

In most of the anti-Trump things I am seeing on /r/politics, the top comment(s) are generally anti-Clinton, or at least more rational about a dislike for Trump based on things he has actually done or said.

It's almost as if there were a group of people who felt that the record needed correcting in /r/politics. So to speak.

Mission accomplished, by the looks of it today.