How partisan voters fuel the influence of public information

•I study sincere voting in large elections characterized by the presence of some partisan voters.•I characterize the set of public signals sustaining the sincere voting behavior.•The presence of partisan voters generates incentives to vote against the public signal.•The set of equilibrium public signals positively depends on the share of partisans.

I study sincere voting equilibria in elections with public information in a large Poisson game. In addition to rational voters, the electorate is characterized by the presence of partisan voters who vote according to their ideological position. I show that the set of public signals compatible with sincere voting becomes smaller as the number of partisan voters vanishes which suggests that, when the number of partisan voters is small, public information hardly manipulates voting decisions.