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Even Republicans aren't sold on President Trump's plan to fund the U.S.-Mexico border wall. CNN reported Friday that a "growing number" of congressional Republicans are leery about the wall's high cost — which could range from $12 billion to $15 billion — and Trump's proposal to have U.S. taxpayers foot the bill initially and then later be reimbursed by Mexico.

Sen. Lisa Murkowski (R-Alaska), who was one of two Senate Republicans this week to announce she'd vote against the confirmation of Trump's education secretary nominee Betsy DeVos, said she would not support the border wall plan if its costs weren't offset by other spending cuts. "If you're going to spend that kind of money, you're going to have to show me where you're going to get that money," Murkowski said. She added, "I don't see how you can get a bill like that through (Congress) without offsets. I don't see how that's possible." Sen. John McCain (R-Ariz.) made it abundantly clear it was "not a viable option" to rely on Mexico to reimburse the U.S., especially since Mexico has repeatedly said it would not foot the bill.

Sen. John Cornyn (R-Texas), meanwhile, isn't convinced the wall can even solve the problems Trump claims it can. "I have concerns about spending un-offset money, which adds to the debt, period," Cornyn said. "I don't think we're just going to be able to solve border security with a physical barrier because people can come under, around it, and through it."