I think there are several positive reasons to vote for Trump.
Some of my Christian friends tell me they can't in good conscience vote for Donald Trump because, when faced with a choice between "the lesser of two evils," the morally right thing is to choose neither one. They recommend voting for a third-party or write-in candidate.
I fully understand that many pastors might never want to endorse a candidate from the pulpit (I have never done so before and I might never do so again). But that should be the decision of the pastors and their churches, just as it was in 1860 when many pastors (rightly) decided they had to tell citizens to vote for Abraham Lincoln in order to end the horrible evil of slavery. When the government censors what pastors can preach, I think it is an unconstitutional violation of freedom of religion and freedom of speech.