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Betsy DeVos, President Trump's nominee for education secretary, is one Republican vote away from not being confirmed. Republican Sens. Susan Collins (Maine) and Lisa Murkowski (Alaska) announced on the floor Wednesday they will oppose DeVos' nomination in the final Senate vote, after voting in the affirmative to advance DeVos out of committee.

"I will not, can not vote to confirm her," Collins said. Murkowski said she has "serious concerns about a nominee ... who has been so immersed in the discussion of vouchers," and noted that she received "thousands" of calls from concerned constituents. If all Democrats oppose DeVos and all remaining Republicans support her, she will secure 50 votes — one short of a majority. In that case, Vice President Mike Pence could step in as a tiebreaker; if DeVos were to lose another Republican vote, however, she would not be confirmed.

In the meantime, the uncertainty over DeVos' nomination will likely stall the confirmation process for Sen. Jeff Sessions (R-Ala.), Trump's nominee for attorney general. Until Sessions casts his vote on DeVos, Republicans are unlikely to hold a vote that would cost them one of their fellow senators with margins on DeVos so thin.

White House Press Secretary Sean Spicer insisted Wednesday that there won't be a problem confirming DeVos. "I am 100 percent confident she will be the next secretary of education," Spicer said.