While Eliot Spitzer scrambles for signatures to enter the Democratic primary for city comptroller, many are musing about what the former governor’s most famous and powerful nemeses will do to block his political resurrection. Yesterday, the power-lunch crowd at the Four Seasons was abuzz about how former NYSE chairman Dick Grasso (whom Spitzer once sued over his $140 million pay package), Ken Langone (whom Spitzer went after as chairman of the NYSE comp committee), and ex-AIG chair Hank Greenberg could unite to block Spitzer or help his rival, Manhattan Borough President Scott Stringer. One source told us, “Look for some very large donations to Stringer’s campaign.”