CHICAGO (AP) — As Democrats debate how to rebuild a winning coalition to take back power in Washington, many political veterans remember when the party was similarly riven — and in time remade — by the insurgent campaign of the late Rev. Jesse Jackson . In two presidential bids, Jackson, who was then the most prominent civil rights leader in the country, mobilized a racially and economically diverse Rainbow Coalition of voters he said reflected the nation’s inherent diversity. While Jackson