Trump tried to run as a conservative, but his liberal side is starting to show. So now the argument for Trump is “Yeah, we know Trump’s not a conservative, but he talks tough and he’s the only one who can win.” Sorry, I strongly disagree that Cruz can’t win, not only do I think he will win, I think he will wipe the floor with Hillary and give the Dems a spanking of 1980s proportions. And even if he doesn’t win, I want to go down swinging for what’s right, I’m supporting the conservative in this race. If we support the populist Trump and compromise our principles to win, what good is it going to do when he takes power and enacts an agenda that is not conservative?
That's basically the same explanation real conservatives offered for not supporting Mittens in 2012: Mittens, if elected, could have done far more damage to the conservative movement, as President and Party leader, than Obama has done.
In addition, he'd have likely tried to pass Romneycare at the federal level (surprise!) because the Fortune 500 |proprietor+manager| class were screaming for a federal excuse to dump employee healthcare costs on the public sector.
And, Romney'd have done it under the aegis of the GOP while calling for "party unity", creating a rightist "PUMA" movement in lieu of the Tea Party. That movement could never, with the e-GOP in adverse possession of both the Party and the Government, have challenged Sovietcare as lucidly and as effectively as the Tea Party has done.