Trump is not going to be nominated (my bet is on Rubio - he ticks more of the boxes than any other candidate) and even if he were he would have no chance of being elected.
Most of the electoral college votes are locked up in safe Republican or Democrat states. Even in their best result in recent decades - 2004, at the height of the war on terror, before Iraq had been shown to be a disaster, and against a truly dire Democrat candidate - the Republicans only cleared the winning threashold by 16 electoral college votes.
To win, any candidate has to try to persuade the swing states, and that means moving away from base-pleasing extremes. It really doesn't matter if Trump is able to pick up 99% of the votes in somewhere like, say, Alabama, because they could slap a red rosette on a turnip and call it the Republican candidate and Alabama would still vote for it. To win, Trump would need to be able to hold all the current Republican states and take big swing ones like Florida.
Trump would be doubly screwed because (a) he is way out to the right of his own party's centre and (b) he is the most Hispanophobic candidate on the slate. Who seriously thinks a platform as racist as his has any chance of winning Florida (a key swing state with 29 electoral college votes)? There have been mutterings that he could cost the Republicans Texas, which has a huge Hispanic population (I can't see that happening, though).
The overwhelmingly most likely outcome of a Trump nomination is a Clinton victory. Analysts know it, the Republican Party elite and big donors know it, and so, perhaps, does Donald Trump.