The race to replace outgoing U.S. Sen. Kay Bailey Hutchison, R-Texas, may only be days old, but at least one candidate in the crowded field is already pulling out the big guns.

Today, former Texas Secretary of State Roger Williams, a Republican, is announcing the backing of former president George H. W. Bush, who will bestow his endorsement at a 3 p.m. press conference at his Houston office.

Williams has had his eye on Hutchison's seat for a while. He did not lose focus even after Hutchison decided to stay in office during her recent unsuccessful gubernatorial bid, which also received the elder Bush's endorsement.

"We announced in January 2009, and regardless of who was in or not, we've never stopped campaigning since then," Williams told the Tribune on the day Hutchison revealed she would not be seeking re-election next year, leaving the seat open.

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