SALT LAKE CITY (AP) -- U.S. Sen. Bob Bennett will face another challenger from within his own Republican Party.
Mike Lee's campaign manager says Lee will announce his candidacy for U.S. Senate on Tuesday.
Lee is an attorney from Alpine who served as general counsel to former Gov. Jon Huntsman.
Bennett is seeking a fourth term but is already facing three Republican challengers: Tim Bridgewater, Cherilyn Eagar and James Williams. So far Sam Granato is the only Democrat vying for Bennett's job.
Another challenger, Attorney General Mark Shurtleff, dropped out of the race to spend more time with a mentally ill daughter. Shurtleff endorsed Lee on Tuesday.
Lee has been testing the waters for a Senate race by giving a series of talks around the state about the Constitution.
Republican delegates will choose the party's nominee in May at the state convention.
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