"Fox News Sunday" anchor Chris Wallace said Friday morning that Judge Brett Kavanaugh’s Supreme Court confirmation remains "on a razor's edge" after the Senate voted 51-49 to advance the nomination to a final vote. 

Three out of four key undecided senators - Susan Collins (R-Maine), Jeff Flake (R-Ariz.) and Joe Manchin (D-W.V.) - voted "yes" to advance the nomination, while Sen. Lisa Murkowski (R-Alaska) voted "no."

Collins is expected to announce her final decision in a speech on the Senate floor at 3:00pm ET Friday. Wallace emphasized that the cloture vote count is not necessarily a clear indication of how the final vote will go.

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A source familiar with the lobbying efforts to confirm Kavanaugh told Fox News that the White House believes it has the votes to confirm Kavanaugh on Saturday. The White House reportedly believes Manchin will vote to confirm Kavanaugh. 

Wallace said Friday's dramatic roll-call vote, with key votes still in question, was "extraordinary" to watch. But he said it's not unheard-of for a senator to vote "yes" on cloture, but flip to a "no" in the final vote. 

Wallace questioned whether Manchin will ultimately side with Republicans if his vote is the difference in Kavanaugh's confirmation. 

"It seems to me this is still on a razor's edge."

Sen. Steve Daines (R-Mont.) is going to be in Montana at his daughter's wedding on Saturday, but said he would fly back to D.C. if he is needed to cast the decisive vote.

Watch the reaction above and don't miss continuing coverage on Fox News Channel.

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