Story highlights Top Senate Republican Mitch McConnell won't say if Donald Trump is qualified for the White House

McConnell praised recent Trump moves like delivering prepared speeches

Washington (CNN) Senate Majority Leader Mitch McConnell wouldn't answer questions Sunday about whether Donald Trump is qualified for the presidency, saying he'll "leave that to the American people to decide."

The Kentucky Republican was pressed on ABC's "This Week" about Trump's lagging poll numbers -- and concerns that a series of controversies, which have included attacking a judge's ethnicity and firing his campaign manager, have left growing numbers of voters believing Trump is unqualified for the job.

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

He praised Trump for firing campaign manager Corey Lewandowski and for increasingly using a teleprompter to deliver prepared speeches, rather than off-the-cuff remarks.

"I think a good step in the right direction was the changes he made in the campaign," McConnell said. "He's beginning to use a prepared script more often, which I think is absolutely appropriate for any candidate, whether you're a long-time politician like Hillary Clinton or whether you're new to the game like Donald Trump."

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