(CNN) President Donald Trump's frequent jabs at Sen. John McCain on the campaign trail have angered fellow Senate Republicans -- particularly McCain's closest friend, Sen. Lindsey Graham.

"I don't think it's appropriate," Graham told CNN on Thursday. "I think it doesn't help the President."

He added, "It hurts the President more than it helps him."

Trump frequently berates McCain by calling out his dramatic vote against a bill to repeal parts of the Affordable Care Act. While the President doesn't call out the Arizona Republican by name, it's clear he's referencing McCain, whom he accuses of going back on his word to repeal and replace Obamacare.

Trump falsely says the Senate was one vote away from repealing and replacing the law. In fact, McCain's vote last year was on a bill designed to eliminate only specific elements of the law -- dubbed "skinny repeal." Moreover, the measure still needed to survive a House-Senate conference committee and final approval in both chambers, anything but a sure bet.

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