Cross-national studies of authoritarian politics find a strong association between elections and regime stability. This is particularly the case in contexts where ethnic- and identity-based divisions are politically salient and incumbent autocrats develop coalitions that comprise large, or dominant, groups. But in many cases, oppositional elites wield considerable power: they command significant electoral support and regularly challenge incumbent autocrats in legislative institutions. This article accounts for opposition strength in terms of the electoral behavior of minority groups and their ability to use ideological labels to appeal to out-group voters. Over time, this strategy increases the likelihood of minority group success and incentivizes candidates who run with ideological labels to oppose incumbent autocrats once in the legislature. Drawing on new data from Kuwait, an oil-rich Arab Gulf monarchy that has held regular elections since 1963, the article explains the endogenous origins of the Kuwaiti opposition. With the onset of mass politics in 1981, the ruling Al-Sabah family's reliance on dominant groups provided it with an important set of allies that promised legislative compliance. However, in response, candidates representing minority groups began using Islamist, liberal, and populist labels in elections. The durability of the Al-Sabah's alliances eroded and oppositional activity became a persistent feature of legislative politics in the Kuwait National Assembly.