Twitter has become an indispensable tool for politicians and officials, including US mayors as heads of local governments, to engage with constituents in real time and convey their political agendas. However, there is limited research on the relationship between the political context associated with the role of mayor and their ways of communication on Twitter. This study explores the Twitter usage patterns of mayors of the 100 largest US cities in the light of two unique political contexts: partisan affiliation and form of municipal government. By conducting a twofold statistical analysis, this study found significant differences in Twitter usage patterns between mayor groups based on political context factors. However, regression analysis revealed that these differences were not caused by political party or form of government, but rather were more related to the city’s size in population. Differences in political context factors were not found strong predictors of the variation of Twitter usage patterns of mayors. The Communication Theory of Identity directs this twist to another potential scenario: identity gaps might exist within the mayors’ layers of identity construct. In addition, factors intrinsic to the city, such as its population size, have a substantial impact on the way mayors communicate on Twitter.