Story highlights Trump's support among the voters most important to his victory is declining

To understand the implications for Trump and his fellow Republicans, tune in to "The Daily DC"

(CNN) A new Quinnipiac University poll reveals an unwelcome development for President Donald Trump: weakening support among the voters that catapulted him to the White House.

"There are some significant cracks in the base of his support," says CNN Political Director David Chalian in Thursday's episode of "The Daily DC ." While just 33% of voters approve of how Trump is performing in office, Chalian explains that the more concerning finding for the President -- and Republican lawmakers -- is his falling support among Republicans and independents, who were crucial to his electoral success last November.

"That's a trigger number," Chalian says.

Trump's approvals on a range of issues have hit record lows in the Quinnipiac survey. More voters disapprove than approve of how the President is handling every major policy issue. Seventy-one percent of respondents say Trump is not level-headed, while 63% say he does not have good leadership skills.

White voters without a college degree, another crucial demographic group for Trump, also disapprove of his performance in the Oval Office.

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