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WASHINGTON (CBSMiami/CNN) – President Donald Trump has sparked new fears he may be trying to squash Special Counsel Robert Mueller’s investigation into possible collusion between the Trump campaign and Russia.

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Amid that Senate Majority Leader Mitch McConnell is still mum on every controversial tweet or other action by President Trump, according to people close to the senator.

While he has complained before about the abundance of tweets, he’s withheld revealing publicly the depths of his concerns.

That was the case this weekend when reporters pressed his staff for a response to Trump’s slamming of special counsel Robert Mueller that caused many Republicans to worry the President might fire the man heading the Russia investigation.

McConnell’s staff would only refer reporters back to a January statement from McConnell when he said he didn’t think Mueller needed any special protection because he didn’t think the President would fire him. The aide said McConnell’s position had not evolved since then.

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But while he was silent, the GOP leader knew the Sunday TV talk shows were filled with members of his Republican conference — from across the ideological spectrum — urging caution to the President and imploring him not to take the drastic step. McConnell could let his members make the point and hold his fire until his weekly news conference Tuesday when he knows he will be asked about the issue, according to a person familiar with his thinking.

McConnell and Trump speak regularly and have a good working relationship, according to Senate aides, something that could be jeopardized if McConnell came out swinging whenever he had a disagreement with a presidential tweet.

His reticence may also mean that when and if McConnell does speak out on some issue at some time, his words could carry more weight than if he was routinely publicized his concerns.

South Carolina Republican Sen. Lindsey Graham, who was one of the strongest voices Sunday against dismissing Mueller, was asked why GOP leaders haven’t been more vocal urging Trump not to fire Mueller.

“They probably feel like they don’t need to say it,” Graham said. “I just think you spend your capital on issues where you think you get your best return. I don’t think anybody in our conference believes Robert Mueller is going to be fired. I don’t.”

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