COLUMBUS, Ohio — Sen. George Voinovich said today he won't seek re-election in 2010, becoming the fourth Republican to make departure plans since the Democratic landslide.

Voinovich said in a statement that challenges facing Ohio and the country will require him to devote all of his energy to serving out his current term. Campaigning and fundraising would take time away from his work as a senator, he said.

Voinovich, 72, also said he wants to spend more time with his family.

He served as mayor of Cleveland and was a two-term governor before his election to the Senate in 1998. He was considered a strong favorite for re-election if he had chosen to seek a third term in 2010.

In recent weeks, Republican Sens. Kit Bond of Missouri, Mel Martinez of Florida and Sam Brownback of Kansas have all announced plans to retire in 2010.