Senate Majority Leader Mitch McConnell (R-Ky.) is supporting Republican presumptive nominee Donald Trump for president -- but he isn't saying, at least for now, whether he thinks the business mogul is actually up to the job.

McConnell twice declined on ABC's "This Week" Sunday to say straight out that Trump is qualified to be president.

"Look, that will be up to the American people to decide," McConnell said. "He won the Republican nomination fair and square. He got more votes than anybody else against a whole lot of well-qualified candidates. So our primary voters have made their decision as to who they want to be the nominee. The American people will be able to make that decision in the fall."

Sixty-four percent of Americans believe Trump is not qualified to be president, versus 37 percent who say Democratic presumptive nominee Hillary Clinton is not qualified, according to a Washington Post-ABC poll released Sunday.

After "This Week" host George Stephanopoulos asked McConnell whether he thinks Trump is qualified, the top Senate Republican said he sees it as a good step that the candidate is using a prepared script more often.

"I think there's no question that he's made a number of mistakes over the last few weeks," McConnell said. "I think they're beginning to right the ship; it's a long time until November. The burden obviously will be on him to convince people that he can handle this job."

He added later that Trump needs to "catch up and catch up fast" on fundraising for his campaign, after dismal finance numbers came out last week.

McConnell said earlier this month that he hoped Trump would select a running mate with more experience and knowledge than himself, "because it's pretty obvious he doesn't know a lot about the issues."

Democrat Tom Perez, the current Labor secretary who has been floated as a potential vice presidential pick for Clinton, unsurprisingly had an easier time answering the qualification question.

"Is Donald Trump qualified to be president?" Perez said on "This Week" Sunday. "The answer is no."