COLUMBUS, Ohio - There could be an open seat in the United States Senate when the 2010 election rolls around.

Current Ohio Senator George Voinovich is expected to announce today in a conference call that he will retire when his term expires after this session of Congress rather than seek reelection.

The Republican, from the Cleveland area, had been expected to seek a third term and had already banked $2.7 million to fund the potential campaign. In the weeks after Christmas, however, he reconsidered.

The 72-year-old Voinovich is the fourth Republican to make plans for departure from the Senate after the Democrats won in a landslide victory in November.

Former Congressman Rob Portman is considered by insiders to be the frontrunner to be the Republican nominee to replace Voinovich.