A word of advice: Don't get your hopes up.

If you want to know how President Donald Trump’s impeachment trial could play out, keep your eye on Lamar Alexander.

... Three GOP senators have expressed some level of support for calling witnesses, and if they joined all Democrats, it would result in a 50-50 tie and likely be defeated. Unless Chief Justice John Roberts shocked Washington by wading in with a tie-break, Democrats need one more Republican to break ranks and upend GOP plans for a swift Trump acquittal.

That’s got both parties eagerly eyeing Alexander. He's a retiring defender of the Senate as an institution who's occasionally bucked his party, but he also counts Majority Leader Mitch McConnell as a longtime ally. He's more hesitant to criticize Trump than are some other Republicans, but he also has said it was "inappropriate" for Trump to ask foreign governments to investigate his political opponents.

... Democrats ... are holding out hope that Alexander will be their hero in the mold of the late Sen. John McCain, whose extraordinary vote derailed the GOP’s effort to repeal Obamacare. Though Alexander would never blindside McConnell the way McCain did, he is widely believed to be a Republican who could be receptive to Democrats’ message that the Senate needs to hear more evidence.

But CNN's Manu Raju is right: There won't be a 51-49 vote for witnesses. There will have to be more than 51 senators in favor.

MANU RAJU, CNN SENIOR CONGRESSIONAL CORRESPONDENT: Well I can tell you, Chris that it's unlikely that there would just be four Senators who would break ranks, if they were to be enough, a majority vote, because no Republican Senator wants to be vote number 51.

If there is enough support in the Senate to subpoena document, subpoena witnesses, there is more likely going to be 53 or 54 votes. That means there would have to be more than four potentially, in order to move forward, maybe five, maybe six, maybe seven, maybe eight, to do just that.

And, at the moment, that is not in the realm of possibility. That could certainly change.

But talking to Republican Senators, people who are on the fence, people who are in Republican leadership, it is highly unlikely, at the moment that they will vote to subpoena witnesses and documents.

Now, that could change because some Members are still holding their cards pretty close to their vest.

Susan Collins has indicated that she would vote to subpoena most likely witnesses and documents, also Mitt Romney has indicated that he wants to subpoena, talk to John Bolton. Lisa Murkowski suggested an openness to it.

But who is the fourth? Who is the fifth? Who is the sixth Senator? Uncertain and unclear, at the moment.

People look at Lamar Alexander, for one, the Tennessee Republican. I've talked to him many times over the last several weeks, and he's taking it very careful, he's very cautious about it. He's a retiring institutionalist.

But he's also very close to Mitch McConnell. He's been critical of the House process too. And there's lot of skeptics that he would be vote number 51.

So, if you're going by the theory that you need to have about 53 Senators in order to move forward, getting the other two is on - who those other people are is unclear.

Even people like a Cory Gardner, who's up for re-election in Colorado, in a swing state, someone - one of the most vulnerable Republicans in the country, he also needs the President's support in order to win reelection.

CUOMO: Right.

RAJU: He has been very circumspect about saying anything critical about the President so far.

So, a lot of questions about whether the Democrats can succeed because their goal right now....

It's not going to happen.

It was never going to happen. I told you on Sunday that Republican senators would inevitably respond to this trial by announcing that they were shocked, shocked, by the Democrats' behavior:

Much of the Senate GOP, along with the White House and the right-wing media, is about to declare that virtually everything the House managers do is a flagrant violation of law, common sense, and the Constitution. Once this happens, even alleged moderates such as Mitt Romney and Susan Collins will join in the fauxtrage -- and you can forget a successful vote to call witnesses or allow further documentary evidence to be considered. The plan is to say that the behavior of the Democrats was so out of bounds that the only way to conclude the process fairly is a vote to dismiss the charges -- and that will happen.

That's more or less what's going on now. We had this after the first day:

Sen. Susan Collins was “stunned” by Rep. Jerry Nadler’s late-night diatribe this week against what he deemed a “cover-up” by Senate Republicans for President Donald Trump — so much so that she wrote a note to Supreme Court Chief Justice John Roberts.

And we had this:

Sen. Lisa Murkowski, R-Alaska, said she was "offended" by House manager Jerry Nadler's comments this week that Republican senators would be involved in a cover-up if they did not agree to call former national security adviser John Bolton to testify in the impeachment trial, one of her aides said Thursday.

And now we have this (admittedly from a non-moderate):

Besides complaints about boredom (“They’ve got about a one-hour presentation that they gave six hours on Tuesday and eight hours yesterday,” Senator Roy Blunt told The New York Times), Republican senators will say that the Democratic case was presented in an offensive manner. The moderates will suggest that they might have voted for witnesses if Democrats had been nicer. So there won't be witnesses.

Published with permission from No More Mr. Nice Blog