Interestingly, I think the Democrats are playing a dangerous game. They want Trump to be powerful enough to win the primary but weak enough to lose in the General election. They are on the record supporting Republican candidates in primaries that they think they will be able to defeat in the General election. IMO, that is election fraud but a topic for another thread.
Trump should be quietly fading away even with his enormous appeal to many voters. It is the Democrats that are keeping him relevant.
When the time comes and Trump is the Republican candidate, just look back at the decisions the Democrats made to make it possible. If, and that is a big if, Donald Trump wins the General Election, it will be the Democrats that made it all possible. Of course, it will divide the nation even more and the Democrats will put on their best "Who, Me?" face.