Trump declined to offer any names during a phone interview on ABC's "Good Morning America." When asked if his VP pick would definitely be a Republican, Trump responded, "Yes, that's true."
"It will probably be a person with political experience," Trumps said. "I do like the political sphere."
Trump said he could handle two of the three major priorities of a president but would need help with the third.
"You have the military sphere, you have the political sphere and you have the business. Well the business I handle. I'm going to be very, very good on the military," Trump said. 
"I think probably I would like to go with somebody with great political experience."
Trump secured a knockout blow in the GOP race with a win in the Indiana primary Tuesday. His last major rival, Ted CruzRafael (Ted) Edward CruzRussia raises problems for GOP candidates Deal to fix family separations hits snag in the Senate O'Rourke calls for Trump's impeachment over Putin summit MORE, suspended his campaign, leaving only John Kasich in the GOP race. The Ohio governor trails Trump by nearly 900 delegates.