POWER CORRUPTS AND running for Mayor of Philadelphia corrupts absolutely. Sometimes a candidate has to bend his principles in order to connect with the wider electoral audience in a citywide race. For instance, Michael Nutter is about as popular with cigarette smokers in the city's bars and nightclubs as an LCB enforcement agent. Will Nutter, who introduced the smoking ban legislation that outlawed cigarette smoking in bars and restaurants throughout the city, compromise himself to gain votes from this crucial cross section of voters? Hey, buddy, gotta light?