Grover Norquist thinks the stakes are high:
Ron Paul is the only candidate for the Republican nomination whose endorsement will matter to Mitt Romney. It is the only endorsement that will bring votes and the only endorsement, if withheld, that could cost Romney the general election. If Ron Paul speaks at the GOP convention (as he was not invited to do in 2008), the party will be united and Romney will win in November 2012. If Ron Paul speaks only at his own rally in Tampa, Florida (as happened at the 2008 GOP convention in Minnesota) the party will not be at full strength.
Don't do it, Ron.