Trump is basically the Non-Mormon Romney.
If you don't like Romney because he's Mormon or a flip-flopper, then Trump may be appealing as a Northeast Liberal Rich guy.
Trump is basically just as liberal as Rudy, but Trump may change his positions on abortion, gun control, gay marriage, environment, for political purposes.
One big difference is Trump has been publicly for
reducing immigration on top of his anti-China stance and criticism of NAFTA the last 12 years or so, plus he's been courting the News Max crowd for awhile now. He appeals to a lot of the 'law and order,' 'seal the border' talk radio crowd for a reason. Of course it's probably all for show given his wife and his contacts and everything, but who cares.