After sending senators home earlier than expected Thursday, Republican negotiators were going to work through the night trying to thread the needle to get 50 or more votes for their tax code rewrite.

Senate Finance ranking member Ron Wyden was giving a lengthy speech criticizing the Republican tax plan after Thurday night’s final Senate vote, but the Oregon Democrat was really serving as the soundtrack over an animated gathering of Republican senators and senior aides.

GOP Sens. Ted Cruz of Texas and Bob Corker of Tennessee were the most visible during the discussion. The normally talkative Corker demurred as he left the floor, suggesting it would be best for him not to talk to reporters as negotiations continued.

Corker has been among the most concerned about the potential deficit impact of the tax overhaul, concerns that only seemed to get more significant after a dynamic analysis from the Joint Committee on Taxation showed a roughly $1 trillion deficit effect.

But improving the score through revenue-raisers in the package’s later years is causing consternation for more conservative members, according to one Republican senator present on the floor during the exchange between Cruz and Corker.