It depends on Trump’s margin of victory in the primaries. If it’s a horse race, and Trump is not confident he will win - then yes - he might have to cut a deal to clinch it -like Reagan did in 1980.
What I don’t understand is why didn’t Reagan pick someone else in 1984 when his popularity was peaking and his nomination was virtually uncontested?
Same with Nixon in 1972. He was about to win a record landslide - he had gotten saddled with deep state Ford after Agnew resigned, but why did he not pick a new running mate after the convention? …. can a popular POTUS running for a second term not pick his own running mate?
Trump knows he’s alienated a huge part of the true conservative, far right base, and will have to move to the left, both in policy and his VP pick, to have any chance in the general.
He himself said last night he doesn’t even expect to hit 50% in Iowa today. None of his supporters were listening though, or understand the implications, because they’re in love with the mirage of him they’ve created in their minds.