It’s the only move left for him to make.
He met with Romney, probably established some conditions for an open endorsement, and the negotiated that and came to terms...whatever they are they will probbaly helop. Thios si the type of thing each of them need to do to ensure that Romney sticks to his commitments.
I think Romney should announce soon who his VP will be (Rubio perhaps) and then, before the conmventiopn, also indicate who he is considering for his cabinet. Like Santorum as AG, Bachman as Health, Education and Welfare, Bolton as Secretary of State, etc.