There's a chance that the majority of voters won't vote this election, so the chances of all candidates are amplified. The usual turnout is 60% for presidential election years, 40% when only state officers and members of congress are elected.
Still, I don't think Trump has much of a chance to win the general election. I think this is going to be a bad year for Republicans, because they are seriously divided. The true conservatives and the radio talk show conservatives can't find much common ground.
-Joe-