Republican Sens. Lisa Murkowski of Alaska and Susan Collins of Maine both announced earlier this week that they would break with their party and vote against DeVos' confirmation. The announcements sent shock waves across Capitol Hill and kicked the lobbying effort on DeVos' behalf into overdrive.
DeVos, her spokesman Greg McNeilly said Friday, is reaching out to lawmakers and has been told by 50 Republican senators that they will vote for her Monday.
Should all 50 Republicans keep to their word and back DeVos, Vice President Mike Pence will be required to break the tie in the Senate and approve Trump's education secretary pick.
The Historian of the United States Senate, the official record keeper of the legislative body, said they have yet to find a case where the Vice President was required to break a tie on a cabinet nomination.
But to ensure confirmation, DeVos -- a powerful Michigan Republican who has relationships with GOP lawmakers across the country -- is making regular phone calls, sending letters and writing emails to senators, McNeilly said.
"All one can do is take them at their word," McNeilly said. "Whether or not you agree with Betsy ... one would hope that a US senator's word is their bond and we have every reason to believe that it is."
DeVos' confirmation has been hampered by persistent ethics questions and a lackluster hearing before the Senate Health committee.
DeVos seemed unaware of federal law enforced by the Department of Education during the hearing, and failed to answer a number of questions from Democrats. She also suggested guns in schools would be needed to fend of grizzlies and chalked up her name being associated with her mother's foundation to a "clerical error."
It turned out that error had persisted for close to 20 years.
Even still, McNeilly and other DeVos aides said this week that they will be happy for DeVos to get confirmed no matter how close it is.
"A W in the column is better than an L," McNeilly said.