In case you're keeping track of high-profile endorsements in the race for the 2012 Republican presidential nomination:
Wednesday, former Massachusetts Gov. Mitt Romney picked up the support of Florida Sen. Mark Rubio. This afternoon in Houston, as NPR's Wade Goodwyn tells our Newscast Desk, former President George H.W. Bush will endorse Romney. Bush's wife Barbara and son Jeb (a former Florida governor) have already said Romney's their candidate.
Former President George W. Bush has not weighed in.