As we say, it always about the math on Capitol Hill.
Sen. Mitt Romney (R-UT) and now Sen. Susan Collins (R-ME) are indicating that they are for witnesses. Sen. Lamar Alexander (R-TN) says he will not support witnesses. Sen. Lisa Murkowski (R-AK) is up in the air.
So, if there are 53 GOP senators, and you go to 51 senators to oppose the witness gateway, they lack the votes. Even if Murkowski is a yes, they are at 50-50 (presuming all Democrats vote yes). That means a tie vote. By rule, a tie vote fails in the Senate.
Chief Justice John Roberts is not expected to inject himself into the issue and break a tie, ala Chief Justice Salmon P. Chase in the 1868 impeachment trial of President Andrew Johnson.
What this means is the die is cast. The Senate will likely block the gateway to witnesses tomorrow night. As Majority Leader Mitch McConnell (R-KY) has the first right of recognition on the floor, he could potentially call votes on both articles of impeachment after the Senate clears the gateway vote. There is also the possibility of more debate on the floor before that. Either way, the trial will end either Friday night, the wee hours of Saturday morning or Saturday during the day at the latest.
If senators vote to open up the gateway to witnesses or documents, you could have a multitude of proposals over the coming hours from Senate Majority Leader Mitch McConnell (R-KY) and Senate Minority Leader Chuck Schumer (D-NY). These are likely various slates of witness proposals. Democrats would like to get GOPers on the record opposing certain witnesses. Democrats would then try to boomerang that vote on vulnerable GOPers this fall and argue that McConnell tilted the playing field in the trial toward the President.
If for some reason the Senate votes in favor of an individual witness, then the trial is far from done. The Senate trial rules require senators to depose the witness in private. That could come in days or weeks. But the trial on the floor will go dark. However, the Senate could consider other business during this period. The Senate would eventually have to vote to summon a given witness to the floor.
The dirtiest secret in Washington right now is that both sides truly want to get out here and escape the trial. Senators and aides are exhausted. Republicans loyal to President Trump want to exonerate him as quickly as possible. Yes, Democrats want witnesses. But Democrats will concede privately that even if they don’t get witnesses, they can deploy the Senate’s decision as a campaign issue. Plus, Democratic senators running for President are up in the ear of Schumer to flee to Iowa to campaign. So, this is why senators from both sides are ready to wrap this up – even if some won’t say that out loud.