The 1960 Presidential Election in Chicago, In the contest between the Incumbent Vice President Richard Nixon and Massachusetts Senator John Kennedy Kennedy's 456,312 vote (27.16%) in the city would give him a sufficient Margin to Carry Illinois by 8,858 votes (0.18%)
Because of the Reputation of Mayor Richard J. Daley's Political machine utilizing any means, including fraud, to win, some republicans sought to Get Nixon to have the votes Recounted, which he refused to do - conceding the election on November 9 the Day after the election.
Regardless, Even if Nixon had won Illinois, Kennedy still would have won the Electoral college with 276 electoral votes