This article seeks to explain the dramatic rise of Pim Fortuyn's right-wing populist party during the campaign for the parliamentary elections in the Netherlands in 2002. Fortuyn succeeded in attracting by far the most media attention of all political actors and his new party won 17 per cent of the votes. This article analyses how this new populist party managed to mobilise so much attention and support so suddenly and so rapidly. It uses the notion of 'discursive opportunities' and argues that the public reactions to Pim Fortuyn and his party played a decisive role in his ability to further diffuse his claims in the public sphere and achieve support among the Dutch electorate. The predictions of the effects of discursive opportunities are empirically investigated with longitudinal data from newspapers and opinion polls. To study the dynamics of competition over voter support and over space in the public debate during the election campaign, an ARIMA time-series model is used as well as a negative binomial regression with lagged variables to account for the time-series structure of the data. It is found that discursive opportunities have significantly affected the degree to which Fortuyn was successful both in the competition for voter support, and regarding his ability to express his claims in the media. Combining these two results, a dynamic feedback process is identified that can explain why a stable political situation suddenly spiralled out of equilibrium. Visibility and supportive reactions of others positively affected the opinion polls. Consonance significantly increased Fortuyn's claim-making; dissonance undermined it. Furthermore, electoral support and negative claims on the issue of immigration and integration in the media by others enhanced Fortuyn's ability to further diffuse his viewpoints and to become the main political opinion-maker during the turbulent election campaign of 2002. © 2009 (European Consortium for Political Research).