Chris Wallace: GOP strategists fear Trump’s attacks on Biden’s mental fitness will backfire at debates

Fox News anchor Chris Wallace warned that President Donald Trump's attacks on Joe Biden's mental fitness could backfire.

The president attacked Biden as feeble and boasted about passing a cognitive test himself that screens for dementia, and Fox News anchor Bret Baier asked his colleague whether Trump was making a risky gamble.

"Just from a political analysis standpoint, is there a danger here of going down this road that he and his supporters do when talking about Joe Biden?" Baier asked. "In other words, all Biden has to do is show up and the bar is very low for him to have a success?"

Wallace agreed, and said he wasn't the only one.

"It's a very good question, and that's what a lot of Republican strategists are worrying about," Wallace said. "You set that bar and the expectations so low for Biden in those three presidential debates, if he shows up and doesn't drool, his supporters can say he had a good debate."

A poll from earlier this month found 52 percent of voters believe the 77-year-old Biden has the mental and physical stamina to be president, while only 45 percent say the same thing about the 74-year-old Trump.

The age-related attacks may already be hurting Trump with seniors, who back Biden by a 14-point margin in a new poll.