Evidence Pack: Does Ranked-Choice Voting Actually Reduce Political Polarization?

The American electoral system is undergoing its most significant mechanical shift in a century. Ranked-choice voting, a system that allows citizens to list candidates in order of preference rather than choosing just one, has expanded from a niche municipal experiment to a statewide reality in places like Alaska and Maine. For decades, the traditional plurality system—where the candidate with the most votes wins, regardless of whether they secure a majority—has been the unquestioned standard. But as political polarization deepens and dissatisfaction with the two-party system grows, reformers have pushed ranked-choice voting as a structural antidote to electoral dysfunction.[3][7]

Yet the reform is facing fierce political headwinds across the country. By 2026, seventeen states have enacted legislative bans against the use of ranked-choice voting, and voters in several states recently rejected ballot measures to adopt it. The debate over the system is often clouded by intense partisan rhetoric, with proponents hailing it as a necessary cure for political toxicity and critics dismissing it as a confusing, disenfranchising gimmick that complicates the simple act of casting a ballot. This backlash has forced election administrators and civic organizations to defend the mechanics of the system in increasingly hostile political environments.[2]

To separate hope from hype, political scientists, legal researchers, and election watchdogs have begun compiling hard data on how ranked-choice voting actually performs in the wild. Instead of relying on theoretical models, these researchers are analyzing decades of municipal election data and recent statewide contests to measure the true impact of the system. This evidence pack examines the academic consensus on three core claims surrounding the reform: its impact on political polarization, its effect on overall voter turnout, and its ability to improve diverse representation in government.[7]

Before evaluating the academic claims, it is essential to understand the underlying mechanics of the system. Under ranked-choice voting, citizens receive a ballot that allows them to rank candidates as their first, second, third, and sometimes fourth choices, rather than being forced to select a single name. When the polls close, election officials tally all the first-choice votes. If a single candidate secures more than 50 percent of those first-choice votes, the election is immediately over, and that candidate is declared the outright winner, just as they would be in a traditional election.[7]

However, if no candidate crosses the 50 percent threshold in that initial tally, the system triggers an automatic instant runoff. The candidate who received the fewest first-choice votes is eliminated from the race entirely. Crucially, the ballots of the voters who chose that eliminated candidate as their top pick are not discarded; instead, those specific votes are transferred to the candidates those voters marked as their second choices. This ensures that a voter's voice still matters even if their favorite candidate fails to gain traction.[7]

This process of elimination and redistribution repeats round by round until one candidate finally secures a majority of the active votes. The mechanical goal of this instant runoff is to ensure that the ultimate winner possesses broad, if not always enthusiastic, support from the electorate. Theoretically, this eliminates the frustrating scenario where a deeply unpopular candidate wins a crowded, multi-candidate field with a mere 35 percent plurality simply because the majority opposition was split among several similar alternatives.[7]

The first major claim made by proponents is that ranked-choice voting reduces negative campaigning and cools the temperature of political polarization. The theory suggests that because candidates need to secure second-choice votes from their opponents' supporters to survive the later rounds of counting, they are heavily disincentivized from launching scorched-earth, negative attacks. If a candidate alienates a rival's base through toxic rhetoric, they risk being left off those voters' ballots entirely, effectively dooming their chances in a tight instant runoff scenario.[4]

The evidence supporting this claim is mixed but leans positive in specific contexts. A 2025 report by the American Bar Association found that the system encourages greater consensus-building and more civil political campaigns, particularly in local municipal elections where candidates often cross-endorse each other to build winning coalitions. Furthermore, the Lugar Center for Bipartisanship recently ranked the congressional delegations from Alaska and Maine—the two states using the system for federal elections—as the most bipartisan in the nation, suggesting the electoral mechanics reward cooperation.[1][4]

However, other researchers caution against viewing the system as a panacea for polarization. A 2024 review noted that in locales that are already deeply polarized along partisan lines, the impact on campaign civility was minimal. A study by the Humphrey School of Public Affairs also concluded that ranked-choice voting fails to significantly reduce the broader, entrenched polarization of the major political parties, suggesting that mechanical tweaks to a ballot cannot easily override deep cultural divides or the influence of nationalized political media.[3][6]

The second major claim is that ranked-choice voting increases overall voter turnout. Proponents argue that by eliminating the "spoiler effect"—the fear that voting for a third-party candidate will inadvertently help a voter's least favorite candidate win—the system empowers citizens to vote their conscience. By removing the strategic anxiety of wasting a vote, advocates believe the system draws more disillusioned and independent voters to the polls who might otherwise stay home during a traditional plurality election. This theoretical boost is a major selling point for civic organizations.[4]

Research from the University of Iowa supports this dynamic, finding significant and substantially higher probabilities of turnout in places that use the ranked system. The study attributes this increase not just to voter enthusiasm, but to heightened direct voter contact. Because campaigns are forced to reach out to a wider swath of the electorate to secure crucial down-ballot rankings, they end up mobilizing voters who are typically ignored by traditional get-out-the-vote operations that focus solely on a narrow partisan base.[5]

Youth turnout appears to see a particularly notable bump under the new system. Multiple studies indicate that younger voters are roughly nine percentage points more likely to cast a ballot in cities utilizing ranked-choice voting compared to traditional plurality cities. Researchers attribute this surge to the increased viability of alternative and independent candidates, which resonates strongly with younger demographics who are increasingly dissatisfied with the binary choices offered by the two major political parties. This demographic shift could have long-term implications for local policy.[1][5]

The counter-argument regarding turnout centers on the phenomenon of "ballot exhaustion" and voter error. Researchers at the University of Pennsylvania found that voters make significantly more mistakes on ranked ballots, increasing the risk of invalidation. If a voter only ranks one candidate who is subsequently eliminated early in the tally, their ballot is "exhausted" and does not factor into the final, decisive round. Critics argue this dynamic can artificially depress the effective turnout of the election, particularly among lower-information voters who may find the ranking process overly complex.[3][6]

The third major claim—that ranked-choice voting increases diverse representation—is where the academic evidence is most robust. Traditional plurality voting often penalizes candidates of color or women who run against each other by splitting a shared demographic base. This vote-splitting frequently allows a less representative, establishment candidate to win with a narrow plurality simply because the opposition was divided among multiple diverse challengers. Ranked-choice voting was designed specifically to mitigate this exact structural disadvantage. By allowing voters to rank multiple diverse candidates, the system consolidates minority support.[1][4]

Data compiled by electoral researchers demonstrates that candidates of color consistently gain more votes in the round-by-round counting process. Because voters can rank multiple candidates from similar backgrounds, these candidates pay no penalty when competing against others of the same racial or ethnic group. This consensus-building mechanism has led to demonstrably more diverse city councils and mayoral offices in jurisdictions that have adopted the reform, providing a clear, measurable victory for advocates of proportional representation. This effect is particularly pronounced in crowded primary elections.[4]

Despite its intended neutrality, the implementation of ranked-choice voting has become highly polarized in its own right. A 2025 study from the University of Illinois revealed a near-linear correlation between Republican vote share and opposition to ballot measures proposing the system. As the reform gained traction, conservative lawmakers framed it as a confusing scheme designed to undermine traditional election integrity, leading to the wave of preemptive legislative bans across red states. This partisan sorting has complicated efforts to expand the system nationally.[2]

Yet, the reform also faces skepticism from the left; the same University of Illinois study noted that ranked-choice voting consistently underperformed expectations even in heavily Democratic-leaning areas. This suggests a broader, bipartisan voter hesitance toward overhauling the fundamental mechanics of how Americans cast their ballots. Voters across the political spectrum often express a preference for the simplicity of the traditional system, even if they acknowledge its structural flaws and tendency to produce unrepresentative outcomes. Change is inherently difficult to sell at the ballot box.[2]

Ultimately, the aggregated data suggests that ranked-choice voting is a powerful mechanical tweak rather than a democratic magic wand. It demonstrably improves diverse representation and alters local campaign incentives, but it requires massive voter education to prevent ballot exhaustion and cannot single-handedly erase decades of entrenched political polarization. As more jurisdictions experiment with the system, the debate will increasingly rely on this emerging empirical record rather than the theoretical promises and partisan fears that have defined the conversation thus far.[7]