Chicago has not had a Republican mayor since 1931, but came close in 1983 when a state legislator named Bernard Epton attracted hordes of lifelong Democrats, only to fall just short of winning. You might assume Epton was a politician of rare gifts. In fact, he had only one. In a race against the first African-American to win the Democratic nomination for mayor, he was white — and that was almost enough to win. In the 1980s, Chicago politics were a bubbling cauldron of racial antagonisms. Harold Washington won in 1983 by mobilizing black voters, who were resentful of their treatment by the white mayor, Jane Byrne, and hungry to gain a new role at City Hall.

They turned out in huge numbers, and 99 percent of them voted for Washington — compared to 19 percent of whites. Race was at the center of the acrimonious “council wars” of his first term, as well as the stormy 1987 election, which Washington won shortly before dying of a heart attack.