Former President George H.W. Bush plans to endorse Mitt Romney at an event Thursday in Houston.
Romney spokeswoman Gail Gitcho says the two will appear together and speak to reporters.
The elder Bush has offered encouraging words to Romney throughout the primary season but had withheld a formal endorsement. Former first lady Barbara Bush has formally backed Romney. She recorded automated telephone calls for him during the primary in Ohio.
Their son, former Florida Gov. Jeb Bush, endorsed Romney last week.