Objective. This article analyzes under what circumstances first-time voters are likely to be influenced by the election campaign or by their opinion prior to campaign in their vote choice. Methods. It uses individual-level data from an original online survey conducted among Romanian first-time voters in the November 2019 presidential election. Results. The results indicate that those who trust politicians, find the campaign informative and use social media are influenced by election campaign. Those with higher political knowledge and interest follow their precampaign attitudes in casting the vote. Conclusion. The study reveals the existence of distinct causal mechanisms for young voters who are influenced at the polls by the election campaign or by their own attitude prior to campaign. This indicates the necessity to include the existence of an opinion prior to campaign in future analytical frameworks about voting behavior.Election campaigns are short periods of time in which candidates spend considerable time, effort, and money to shape what citizens think about them (Fridkin and Kenney, 2011). They generate news coverage, informative material, and persuasive messages that can influence citizens' preferences, evaluations, and vote intentions (Ansolabehere and Iyengar, 1994;Nadeau et al., 2008). Campaigns make the electorate more knowledgeable and increase both the external and internal efficacy of voters (Hansen and Pedersen, 2014). Extensive literature indicates that many individuals decide how to vote based on the content of election campaigns (Peterson, 2015). At the same time, another strand of literature argues that campaign effects are limited and previous preferences, partisan dispositions, or political context outside the campaign may drive people's decisions how to vote (Hillygus and Jackman, 2003). The theory of campaigns' minimal effects goes back to more than half a century (Campbell et al., 1960) and claims that voters select a candidate before the campaign begins, mostly by identification with that person (Levine, 2005) and in accordance with their own preferences and values (Ha and Lau, 2015). As such, individual votes can be predicted based on voters' attitudes prior to the campaign (Gelman and King, 1993). In this sense, voters' partisanship is one important determinant that makes the campaign effects fade.So far, the debate about campaign effects has sought to provide evidence at the level of the entire voting population. There is little empirical evidence about these effects on the first-time voters. This category is special for two reasons. First, since they could not vote before, this is the first election campaign to which they have been subjected and arguably