There will be a lot of crossover voters if Trump is the candidate just like Reagan had in the 80s. The Dem voters are voting for a government check. One more term for the left wingers and this country will be bankrupt. Smart Dem voters will understand this and vote for the conservative. Should be more than enough for a Republican win
Reagan didn’t replace his base with Democrats. Besides, no evidence what you said will happen. In head to head match ups, he loses to Hillary. And even worse, his negatives are record level
Reagan was well behind Carter right after the primaries and he won overwhelmingly. If the Republicans do not support Trump if he wins the nomination then they deserve the socialism, that will surely come. I suspect when it comes to a Clinton Presidency or a Trump Presidency they will go with Trump.