[3][4] Hatcher unseated incumbent mayor A. Martin Katz in the Democratic Party primary.

Usually, in the heavily-Democratic city, winning the Democratic nomination was tantamount to election.

[5] However the race was much closer in 1967 due to intense racial politics and the Democratic machine's anger over Hatcher's nomination, being a reformer.

[6] Due to the intense racial divide and the desire of white ethnic Democrats to maintain their grip on power over the city's Democratic machine and patronage system, prominent Democrats in the county machine (including the chairman of the Lake County Democratic Party) endorsed Republican Joe Radigan and worked to purge black voters from voter registration rolls and replace them with non-existent white voters, smashed voting machines in black-majority precincts, and employing white police officers to intimidate black voters from entering voting stations.

[7] While Black Americans made up 53% of Gary's population, white residents had an edge in voter registration.