Pittsburgh Mayor Ed Gainey was ousted Tuesday in a stiff Democratic primary challenge from Corey O'Connor, the son of a former city leader who had the support of the party's "old guard" and some Republicans.Mayor Ed Gainey, seen as the progressive in the race, began the contest on roughly even footing in terms of campaign funding, but O'Connor, son of the late former Mayor Bob O'Connor, had outraised and outspent the incumbent by April – ultimately putting up a fight in a city that has not been competitive on a partisan level since the 1930s.O’Connor received support from some Republican