A Glen Dale native and daughter of former governor Arch A. Moore Jr., Capito began her political career in the West Virginia House of Delegates before winning the Second District seat in the U.S. House of Representatives in 2000. She became the first Republican from West Virginia in the House since the 1980s and the second woman to represent the state in Congress. Serving from 2001 to 2015, she held key committee positions and helped sponsor the Medicare Prescription Drug Benefit.

In 2015, Capito made history as the first woman elected to the U.S. Senate from West Virginia. Re-elected in 2020, she served as ranking member of the Senate Environment and Public Works Committee. By 2024, Capito had become chair of the Republican Policy Committee, a top-ranking role in the Senate and within her party.