Senate Republicans think President Trump is playing a constructive role in the tax debate and are optimistic about their chances of winning a big legislative victory.

Trump flexed his muscle as an advocate on Capitol Hill Tuesday when he took on Sen. Ron Johnson (R-Wis.) during a private meeting after Johnson threatened the day before to vote against the tax bill.

“He told him to stop blocking it and to work out his concerns with the rest of the conference. He told him he would have a chance to offer amendments and he should stop being an impediment,” said a Senate GOP source familiar with the meeting.

“He went at him twice by name,” the source added.