Former New Hampshire Sen. Bob Smith is running for Florida's open U.S. Senate seat.

Smith made the announcement Monday.

He has lived in Sarasota for seven years after serving two terms as U.S. senator from New Hampshire.

His spokesman, Carl Grooms, says Smith, a Republican, was sitting on the sidelines and ready to retire, but became frustrated "as a true conservative with the direction the country was going."

Republicans seeking the seat are Gov. Charlie Crist and former House Speaker Marco Rubio. U.S. Rep. Kendrick Meek is the top Democratic candidate for the seat Republican Mel Martinez is leaving after one term.