Much of the criticism, from high-profile Republicans including Sen. John McCainJohn Sidney McCainGOP rushes to cut ties to Moore GOP strategist: 'There needs to be a repudiation' of Roy Moore by Republicans World leaders reach agreement on trade deal without United States: report MORE (R-Ariz.), has raised concern that the lack of unity around one nominee is strengthening President Obama’s reelection chances.

“I guarantee you that June, July, August, September, October, it's going to seem like an eternity [ago] and no one's going to be worried by the fact that we didn't have a nominee until March or April,” he said. He noted that in 2008, McCain did not officially become the GOP nominee until mid-March.

“You know you're really only looking at, from when John McCain was the nominee, maybe an extra 30 days,” he predicted, basing his estimate on the delegates involved in upcoming primary votes.  

But he also said that the unpredictable race has been good for the party.

“I just happen to believe that having a nomination process that people are talking about, given the difficulty in beating an incumbent president, and given the issues that are at stake in this country, I like my chances better under that scenario than four years ago and putting the world to sleep with our nomination process,” he said.

He dismissed the speculation that the process could lead to a brokered convention, which could be triggered if one of the candidates doesn't accumulate a majority of the delegates before the GOP assembles in Tampa on Aug. 27.