Trump has to choose between two strategies. First, he could decide to name his running mate well before the convention and choose someone many of his most ardent opponents inside the Republican Party will like. Based on the bad blood between Trump and Senator Ted Cruz, and the fact that most elected Republicans don't like Cruz either, I don't see Cruz being a viable choice. Governor John Kasich is a bit more of a plausible choice, and some GOP insiders seem to think Kasich has been angling for the VP slot all along. And he offers the hint of general election help with his popularity in the crucial state of Ohio. But Kasich's many recent comments disparaging Trump and even saying he's not fit to be president are going to be hard to ignore. Still, it would be hard for Trump to do better in his attempts to appear more conciliatory than he could by finding some way to join forces with Kasich.
On CNBC Wednesday morning, Steve Forbes put forth the possibility that Trump will pick a wildcard running mate like former Secretary of State Colin Powell. But Powell has almost completely left the Republican Party and it's hard to believe the very moderate in philosophy and demeanor Powell will come back to join the bombastic and divisive Trump.