This article did a great job. It itself did everything that drives the support behind Trump.
There is in my mind only one candidate who stands a chance at this point in beating Trump in a national campaign: Bernie Sanders.
This is because Sanders understands something that none of the other politicians do. If you call Trump racist, sexist, homophobic, or whatever he will only grow stronger. You need to oppose him on his issues and not from a position of authority.
Trump gains his appeal from being a genuinely good entertainer, having recovered from many bankruptcies, how he speaks to his supporter, and his anti-establishment nature. He presents himself, and also acts as if, he is just the average guy even going so far as to call people up to the stage. This strengthens his presentation that he is not a "bought" candidate.
When someone from the establishment criticizes him, they validate all of his claims. He is the anti-establishment character: the only people who can push against him are people who aren't part of the establishment.
Remember that all press, is good press.
If you stick to the issues, don't let him get any sound bytes in, and stop talking about how evil he is 24/7 then he will no longer have any power in the race.
