(CNN) - Asked Thursday what Mitt Romney wants his running mate to say about the presumptive GOP nominee, the candidate said he's looking for someone with "strength of character."
"I don't think I have anything for you on the VP running mate," Romney said in an interview on NBC News. "I certainly expect to have a person that has a strength of character, a vision for the country that adds something to the political discourse about the direction of the country."
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He continued: "I happen to believe this is a defining election for America, that we're going to be voting for what kind of America we're going to have."
With less than three weeks left before the Republican National Convention, speculation over Romney's potential vice presidential nominee has picked up momentum among the political establishment.
But Romney and his campaign have remained tight-lipped, with only the candidate, his wife, Ann, and his adviser, Beth Myers, knowing the full details of the decision process.