Trump's approval rating in Israel is very high and considering how much they control the GOP and network donors the answer is he has no chance of being dethroned in primaries. He is an incumbent and will have more money than any of his challengers by far. He probably won't spend any of his own money this time around either. I would like to see him get primaries, but that list right now includes candidates that are all unelectable against Trump or most democrat candidates. I doubt any one of them even have above a 50% approval within the party. Bob Corker and John Kasich are extremely unpopular among their own voting base right now.
According to Fortune, he spent $66 million of his own money out of the $339 million raised. So he funded about 20% which probably qualifies as the largest individual contribution since Ross Perot in the 90's and one the highest of the modern political era.
He's already garnered more than $70 million in donations as of February. That's way more than any other past president at this point in his term (Obama had the previous record of $3.3 million at this same point after first election). I definitely don't see him putting up 20% this time around...if any at all.
Massimus - "Trump already has democrat support."