Five months after Gov. James McGreevey left office in disgrace, a new public opinion poll shows that 49 percent of New Jerseyans would consider voting for him in a future election. The poll by Zogby International was commissioned by the gay rights advocacy group Garden State Equality to measure public support for gay marriage (which remains at 55 percent statewide). The group piggy-backed the McGreevey question onto the poll, largely in an effort to test electoral support for gay and lesbian candidates.