When Sen. Mitt Romney said on Tuesday that he would support the Senate moving ahead with the confirmation of a Supreme Court nominee from President Trump before the election, he tipped the balance of the tenuous confirmation math in Republicans' favor, opening a lane for a nominee to clear the Senate with at least 50 Republican votes and Vice President Mike Pence to break the tie.

Hours later, Sen. Pat Toomey, R-Pa., the only other apparently outstanding possible GOP defector, said he supported moving ahead with a nominee as well. That left Sens. Susan Collins, R-Maine, and Lisa Murkowski, R-Alaska, as the only two Republicans to say they would oppose immediately moving ahead with a Trump nominee.

"My decision regarding a Supreme Court nomination is not the result of a subjective test of ‘fairness’ which, like beauty, is in the eye of the beholder," Romney, R-Utah, said in a statement. "It is based on the immutable fairness of following the law, which in this case is the Constitution and precedent. The historical precedent of election year nominations is that the Senate generally does not confirm an opposing party’s nominee but does confirm a nominee of its own."

MITT ROMNEY SAYS HE SUPPORTS MOVING AHEAD WITH TRUMP SUPREME COURT NOMINEE

Added Toomey: "I will evaluate President Trump’s nominee to replace Justice Ruth Bader Ginsburg based on whether the nominee has the character, intellect and experience needed to serve on our nation’s highest court. These are the same objective, nonpartisan criteria that I have used to evaluate judicial nominees under both President Obama and President Trump."

The statements from Romney and Toomey on Tuesday, and commitments from a bevy of other Republican senators who are either moderates or electorally vulnerable in the preceding two days, seemed to confirm the hypothesis from Senate Judiciary Committee Chairman Lindsey Graham, R-S.C., that Republicans have the juice to get a nominee across the finish line.

"We've got the votes to confirm Justice Ginsburg's replacement before the election," he told Sean Hannity Monday night. "We're going to move forward in the committee, we're going to report the nomination out of the committee to the floor of the United States Senate so we can vote before the election. Now, that's the constitutional process."

TOOMEY SUPPORTS MOVING AHEAD WITH FILLING SUPREME COURT SEAT VACATED BY GINSBURG

Republicans can afford to lose three votes from their own party and still be able to confirm a nominee. Collins and Murkowski make two. And it appears unlikely that two more Republican senators, having expressed no procedural qualms about timing, would vote against a Republican-nominated justice.

But there is still a long way to go in the confirmation process, starting with Trump actually nominating somebody for the Senate to confirm. Then the nominee will go to committee and be vetted intensely by senators and the media. Then there will be a hearing. And a committee vote. And finally a floor vote. And that's all if things go according to plan for Republicans – they didn't with Justice Brett Kavanaugh in 2018.

"This legislative process and the confirmation process, it's adverbial. It's something that unfolds. And that means it changes as people act and react to one another," R Street Institute senior fellow for governance James Wallner told Fox News. Wallner is a veteran Senate staffer who's served in various roles working for Sens. Toomey and Mike Lee, R-Utah, and former Sen. Jeff Sessions, R-Ala.

Wallner added: "I think it all depends on if the Democrats are willing to use the different procedural tools they have at their disposal as leverage to try to somehow change the narrative."

MCCONNELL WARNS OF DIRTY TRICKS FROM DEMS AS SCHUMER SAYS GOP HAS 'NO RIGHT' TO FILL SUPREME COURT VACANCY

That effort's already started. Senate Minority Leader Chuck Schumer, D-N.Y., on Tuesday and Wednesday got a head start on reaching into his bag of parliamentary tricks.

On Wednesday, for example, Schumer put vulnerable Sen. Kelly Loeffler, R-Ga., on the spot as she led the Senate proceedings for the day.

"I have a parliamentary inquiry for the chair," Schumer said. "Is there a Senate precedent for confirming a Supreme Court nominee between July and Election Day in a presidential year?"

"Materials from the offices of the Secretary of the Senate do not show such a precedent," Loeffler replied.

"Thank you, madam president," Schumer said. "As you just heard, not from the Democratic leader, but from the records of the Senate as spoken by the chair, there is no, no, no precedent for confirming a Supreme Court justice between July and Election Day."

And Tuesday, Schumer blocked the Senate Intelligence Committee from holding a briefing on election security after Senate Intelligence Committee Chairman Marco Rubio, R-Fla., asked for unanimous consent to hold the meeting despite a rule restricting when Senate committees can convene while the chamber is in session.

"Is there objection?" Romney, who at the time was chairing proceedings, asked.

REPUBLICAN SENATORS FALL IN LINE TO BACK MOVING AHEAD WITH TRUMP SCOTUS PICK: 'WE'VE TO THE VOTES'

"Reserving the right to object. Because the Senate Republicans have no respect for the institution, we won’t have business as usual here in the Senate. I object," Schumer said.

Senate Majority Leader Mitch McConnell, R-Ky., decried Schumer's action as a "temper tantrum" on Wednesday.

"Two days ago, the Democratic leader threatened that if the Senate majority dares to play by the rules and behave like a Senate majority, it would mean ‘the end of this supposedly great deliberative body,'" McConnell said. "Yesterday, we learned what he meant. We saw important Senate business hurt by what amounted to a temper tantrum. For some reason, the Democratic leader decided to vent his frustration by blocking the Intelligence Committee from holding a bipartisan counterintelligence hearing."

Wallner also mentioned an option for Schumer could be pressing a vote "to discharge the Judiciary Committee of further consideration of this nominee" immediately after the nominee gets to the Senate. That would essentially mean that the Senate would vote on whether to skip the Judiciary Committee review process and immediately vote to confirm the nominee.

"Those votes are interesting because all of a sudden you have Schumer saying, 'This is a charade. Republicans, let's call it for what it is," Wallner said. "It puts a lot of pressure on people like [Cory] Gardner and Romney. But also people like [Chuck] Grassley...  All of a sudden, you've got a lot of Republicans joining Democrats voting no on what is essentially a symbolic vote that says we should confirm this justice immediately, then that changes the narrative."

CLICK HERE TO GET THE FOX NEWS APP

"Bottom line... Democrats can force votes if they want to. And votes focus attention. They invite outside involvement. They really channel pressure toward certain senators and ultimately change the dynamic," Wallner said. "Even if they call your bluff, then you have a month to talk about COVID again."

But no matter what roadblocks Schumer and Democrats throw up or pitfalls they try to get Trump's eventual nominee to fall victim to, it takes a simple majority in the Senate to confirm a Supreme Court justice. And as things stand right now Republicans appear to have enough senators willing to consider a Trump nominee.

Nothing will be a done deal until there is a final roll call vote to put the new justice on the bench. But right now there is certainly a lane for a Trump nominee to make it through the Senate.

Fox News' Chad Pergram contributed to this report.