As the Senate prepares for another long day of Q&A, Republicans seem increasingly confident that at least 51 senators will vote Friday to prevent bringing additional witnesses into President Trump’s impeachment trial.

The bottom line: The whip count is still fluid, but GOP senators are far more optimistic after yesterday's eight-hour session than they were following their closed-door meeting on Tuesday.

What we're hearing: The Tuesday night meeting was strategically timed — and played exactly the role that Republican leaders had hoped it would.

Sources familiar with the meeting tell Axios that Senate Majority Leader Mitch McConnell told his conference that they did not yet have the votes to block witnesses, knowing that the news would likely leak to the media and alarm some senators who dread both a prolonged impeachment trial and Trump's Twitter wrath.

McConnell and Majority Whip John Thune knew that while it was true that several GOP senators had yet to make clear what their position was, they were confident they could still reach the magic number of 51 no-votes by the end of the week.

The sources say the leaders thought addressing the conference in a secretive setting would dial up the pressure for them to commit to sink the vote, and according to my conversations with senators the next day, the strategy appeared to work.

What Republicans are saying [Corrected]:

Sen. Martha McSally: " I have heard enough. It is time to vote."

I have heard enough. It is time to vote." Sen. Cory Gardner: "I do not believe we need to hear from an 18th witness."

"I do not believe we need to hear from an 18th witness." Sen. Pat Toomey: "I’m very, very skeptical that ... criteria is going to be met" to call more witnesses.

Worth noting: Senators face another eight hours on the Senate floor this afternoon, and there's always a chance that the arguments made by Trump's defense team or House prosecutors could sway key senators in a different direction.