Rep. Nancy Mace, R-S.C., said her Monday will be spent swiftly introducing a resolution calling on Vice President Kamala Harris to invoke the 25th Amendment following President Joe Biden's withdrawal from the presidential race Sunday afternoon.

"If Joe Biden does not have the cognitive ability to seek reelection, he does not have the cognitive ability to serve the remainder of his term," she wrote on X.

President Joe Biden's brother Frank told CBS News on Sunday evening he is "selfishly" glad his brother dropped out of the race, to "have him back for whatever time we have left."

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