(CNN) Several Republican senators said Monday they had not seen anything "new" that changed their stance on the impeachment inquiry into President Donald Trump and there wasn't anything impeachable in the President's behavior, despite dramatic testimony by senior State Department officials and other Trump administration aides over the past few days.

GOP senators also repeatedly complained about what they call the "partisan" handling of the probe by House Democrats.

Senate Majority Leader Mitch McConnell remained silent when he was pressed by a reporter in the Capitol if he was concerned about the testimony -- including from former US Ambassador to Ukraine Marie Yovanovitch and Ukrainian Embassy official David Holmes -- that Trump had demanded Ukraine agree to investigate Joe and Hunter Biden before releasing almost $400 million in aid to the war-torn country.

Earlier in the day, at an event in Louisville, the Kentucky Republican predicted impeachment in the Democrat-controlled House would not lead to his removal in the GOP-led Senate, and he lamented that the Democrats' focus on impeachment was preventing progress on Congress's legislative agenda.

"It doesn't look like there is anything new," said Sen. John Thune, who is second to McConnell in the Republican leadership. "People can disagree about the way the President does things but it doesn't seem like in the court of public opinion people's minds are being changed by anything that's come out so far."

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