(CNN) Senate Republicans find themselves boxed-in in the wake of President Donald Trump's renewed attacks on the late Sen. John McCain, unwilling to strongly stand up to a President who is widely popular with GOP base voters but still deeply uncomfortable with his criticism of the late war hero and, for many in the chamber, a friend.

That fine line Republicans are walking was on display this week when only a few of them weighed in on Trump's sustained assault on McCain and those who did speak out issued tepid statements that praised McCain's military and political service to the country but stopped short of criticizing Trump for his harsh rhetoric.

The clearest example of this came from Sen. Lindsey Graham, a South Carolina Republican, who is known as McCain's soul mate in the Senate but who is also up for re-election in 2020 and in need of Trump's continued political backing.

Speaking in a subdued voice, he told WLOS TV in Spartanburg Wednesday that he is not happy with Trump's attacks on McCain but that, "I'll try to continue to help the President."

"I think the President's comments about Sen. McCain hurt him more than they hurt the legacy of Sen. McCain," Graham said. "My job is to represent the people of South Carolina. They want me to work with the President where I can. I've gotten to know the President. We have a good working relationship. I like him. I don't like it when he says things about my friend John McCain."

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