FILE PHOTO: U.S. Senator Thad Cochran takes part in a news conference at the U.S. Embassy in Havana, Cuba, February 22, 2017. REUTERS/Alexandre Meneghini/File Photo

(Reuters) - A conservative Mississippi state official, Cindy Hyde-Smith, was named on Wednesday to serve as a U.S. senator until a special election in November to replace 80-year-old Thad Cochran, who is retiring because of ill health.

Hyde-Smith will be the first woman to represent Mississippi in Congress. She was the first woman elected to statewide office in Mississippi in 2011 when she won the position of state agriculture and commerce commissioner.

Mississippi Governor Phil Bryant announced the appointment, calling Hyde-Smith a “rock-solid conservative.” He said the appointment would be effective April 2, the day after Cochran is to step down after 40 years in the U.S. Senate.

Cochran welcomed the selection of Hyde-Smith, saying in a statement that she was “a very well-qualified person whose experiences and excellent character will benefit our state in Washington.”

Cochran’s retirement put another Senate seat in play for November’s mid-term elections. One-third of the seats in the Senate and all the seats in the U.S. House of Representatives will be decided.

Both of Mississippi’s U.S. Senate seats will now be up for election. Republican Senator Roger Wicker is running for re-election. Cochran’s seat had not been scheduled for an election until his decision to retire.

In announcing her acceptance of the Senate appointment, Hyde-Smith said she would be a candidate for the seat in the Nov. 6 special election and underscored her record, saying she had “been conservative all of my life” and had a “conservative voting record” for three terms as state senator.

Tea Party state Senator Chris McDaniel, who gave Cochran a scare in a bitterly fought Republican primary in Mississippi four years ago, announced earlier this year that he would run against Wicker. He said Wicker, like Cochran, was part of the Republican establishment.

But after Cochran’s decision to retire, McDaniel announced he would run for Cochran’s seat instead. If McDaniel does run, he and Hyde-Smith would contest a Republican primary.