Former President George H.W. Bush is expected to formally endorse Mitt Romney, adding to the long list of heavy-hitting party figures backing the Republican presidential front-runner. 

The Romney campaign confirmed the endorsement to Fox News. 

Separately, the office of the former president confirmed that Bush and Romney would meet Thursday in Houston, without commenting on specifics. 

The elder Bush has offered support to Romney before and in December seemed to all but endorse the former Massachusetts governor. This would make it official. 

Former first lady Barbara Bush has formally backed Romney, as has their son, former Florida Gov. Jeb Bush. 

The backing is the latest in a string of prominent Republican figures to come out in favor of Romney over the past week, as Rick Santorum and Newt Gingrich stay in the race and try to deprive Romney of the delegates needed to clinch the nomination before the convention. 

Earlier in the week, Romney won the support of House Republican Whip Kevin McCarthy, R-Calif., as well as Tea Party-backed Sen. Mike Lee, R-Utah.