Romney states + Florida + Iowa + Wisconsin + Ohio = 269 EVs (a tie, throwing the election to the House of Representatives, where we win)
Florida is an absolute must win state for any Republican. Romney came very close.
The other three are winnable midwestern states. We have been improving in those states in terms of Gov., Sen., Congr. and state legislature. These states argue for Kasich or Walker to balance the GOP ticket. Perhaps Joni Ernst if you’re looking for a female candidate. A midwestern running mate isn’t a guarantee. Ryan didn’t enable Romney to win the midwest in 2012.
As for Trump, I would give the exact same answer. In spite of being from New York and being a social moderate, he has zero chance of carrying that state or other such states in the absence of a landslide victory.
NOTICE: An expanded map would include Pennsylvania, Virginia, Colorado, Nevada, New Hampshire, Maine-2 and converting Michigan to district method.
FL and OH are going to go Republican regardless of the nominee this cycle.... WI, wouldn’t bet the farm on that at all if they have Kasich or Cruz on the ballot.