Lt. Gov. David Dewhurst (R) has entered the Senate race, ending months of speculation that he would join the crowded GOP field for retiring Sen. Kay Bailey Hutchison’s (R) seat.

Dewhurst campaign manager Jim Bognet told the Associated Press on Tuesday that the campaign paperwork was filed with the Federal Election Commission.

The lieutenant governor joins a crowded Republican field. Former Texas Solicitor General Ted Cruz, former Dallas Mayor Tom Leppert and Railroad Commissioner Elizabeth Ames Jones are running, and state Sen. Dan Patrick is considering a bid.

However, Dewhurst is by far the best-known GOP candidate in the field. Local Republicans say because of this and the large personal wealth he can put toward the campaign, he’s the instant frontrunner in the race for Hutchison’s seat.