Heuristics in Voter Behaviour: Zohran Mamdani’s 2025 N.Y.C. Mayoral Campaign
Jimena Regidor Méndez
Nowadays, it is widely thought that in electoral competitions, voters make rational and informed decisions, based on previous research. However, this is not necessarily the case. Empirical research has shown how people are constrained by time limits, information, attentions, and cognitive capacities to process information. In this bounded rationality context, voters often rely on mental shortcuts, otherwise known as heuristics, to make their decisions faster. We can observe how heuristics have influenced voter behaviour in many political campaigns, but the 2025 N.Y.C. electoral campaign is an exemplary one, as the newly elected mayor has likely been chosen by many who relied on these shortcuts. This is further substantiated by experimental work carried out by Galli et al. (2025), which proves that voters often avoid acquiring factual information even when it is easily available and instead rely on heuristics.
Due to bounded rationality, people intend to make rational choices, but the limitations force good-enough decisions, so they end up satisficing instead. Elections are quite complex, with many candidate issues and arguments, making it impossible to evaluate all options fully. In the case of N.Y.C., this is evident, with all the media saturation and decisions by ranking, which results in voters depending on shortcuts. Moreover, according to Galli et al. (2025), when the costs to acquire information in candidates are low, information searches decrease dramatically, making voters decide with the minimal facts and increasing their chances to make errors. On top of that, voters don’t often update their beliefs when new information becomes available.
The availability heuristic refers to the idea that people judge the importance of issues based on how easily examples come to mind. In elections, this means that the most repeated, vivid issues become the priority. Mamdani’s campaign emphasized rent freezes, free buses, and the affordability crisis, with N.Y.C. as the most expensive city in the U.S. These messages have circulated on speeches, social media, news, and even door-to-door canvassing, which has made them easier to recall and, therefore, a top priority. Thanks to this, voter associated him with solutions to these everyday problems and favored him over his opponents.
As per the representativeness heuristic, people categorize a candidate based on similarity to a prototype, not a full analysis. Mamdani has shown himself as a new generation progressive, grassroots, young, etc. The media has also portrayed him as a socialist democratic immigrant and contrasted him with the “old-guard”: the other candidates and, especially, Andrew Cuomo. All these traits are often associated with change, and when mixed with symbolic matching, one can assume Mamdani’s values & priorities without deeper policy research, just because he matches a prototype. This is the reason why many have favored him.
The anchoring heuristic explains that the first information we receive forms a reference point, and that the later information we are given is judged in relation to it. In elections, this means that a big first impression sticks. The mayor made early big promises, which established high standards (new anchors) that reset voter’s expectations. Mamdani compromised, but what is “reasonable” was set higher. Because of that, the other candidate’s lower-level policies appeared inadequate in comparison.
Building on what the heuristics had established, we can identify other supporting cognitive processes. Selective information avoidance tells us that voters avoid gathering new information and thus rely on shortcuts. The insights of Galli et al. (2025) highlight how this makes voters rely on initial impressions. Besides, there has also been framing, with housing becoming an issue of morality and working-class displacement, underlying the necessities of Maslow’s Pyramid’s last row. This increased the emotional salience, reinforcing the availability heuristic. Finally, through the cognitive bias, people tend to accept information that confirms their previous beliefs, and contradictory information is unlikely to change them.
Having all this into consideration, we can agree that voters rarely research deeply; they prioritize salient issues, evaluate candidates via prototypes, and retain their first impressions, which are difficult to change. When a leader knows how to use heuristics to their advantage, they will repeat their cases to create availability, hit early to be the ones who set anchors, and construct an identity narrative to shape representativeness. Mamdani has done so commendably, which is likely to have affected his 50.4% turnout. This proves that heuristics deeply affect voter’s behavior and knowing how to control the narrative can prove to be very beneficial in electoral campaigns.
