On October 30, 1973, the House began a process to impeach President Nixon. The House Judiciary Committee voted along party lines to issue subpoenas and organize staffers. Four months later on February 6, 1974, the formal process was authorized in a nearly unanimous vote. Nine months later on November 5, 1974, the Republicans lost 48 seats in the House and four seats in the Senate.
https://thehill.com/opinion/white-house/468068-specter-of-nixon-impeachment-looming-over-republican-party