Gov. Paterson avoided the tequila shots and stayed sober at a birthday party for a political staffer at Gramercy Park bar 3 Steps the other night. Although witnesses claimed that guests were downing shots at the Second Avenue bar, a manager told us the governor drank Diet Cokes all night. He added, “Paterson stayed for an hour or two talking politics with partygoers, shaking everyone’s hand and getting pictures with everyone he could.”