Sen. John Ensign, R-Nev., resigned Wednesday as leader of the Republican Policy Committee after admitting Tuesday to having an affair.
Ensign called Senate Minority Leader Mitch McConnell today to offer his resignation from the No. 4 post. McConnell accepted.
"He's accepted responsibility for his actions and apologized to his family and constituents," McConnell said in a statement. "He offered, and I accepted his resignation as chairman of the Policy Committee."
Ensign will remain in the Senate.
On Tuesday Ensign -- a rising Republican Party star who has been discussed as a possible 2012 presidential candidate -- made the announcement of his affair in his home state of Nevada.
"Last year I had an affair," Ensign said in a Las Vegas news conference. "I violated the vows of my marriage. It is the worst thing I have ever done in my life. If there was ever anything in my life that I could take back, this would be it."
"I take full responsibility for my actions," he said.
On Wednesday, the Nevada Republican Party responded to the senator's announcement.
"This is a personal matter and the Nevada Republican Party's thoughts are with Senator Ensign, his wife Darlene, and his wonderful children as they go through this difficult time," said the Nevada Republican Party's Cameron Phillips in a statement.
Ensign's wife, Darlene, also issued a statement.
"Since we found out last year we have worked through the situation, and we have come to a reconciliation. This has been difficult on both families. With the help of our family and close friends, our marriage has become stronger. I love my husband."
Ensign voted to impeach former President Bill Clinton in 1998 on charges related to the cover-up of his affair with intern Monica Lewinsky.
ABC News' Rick Klein contributed to this report.