Volt is a pan-European, Eurofederalist party that seeks to deepen and democratize European Union integration. It participated in elections in nine European countries and won representation in the Dutch Parliament and German constituency for the European Parliament. We examine Volt Netherlands, which studies the possibilities of a pan-European party. We look at the importance of its pro-European positions for voting for this party; this is an issue that all national branches of Volt share. We also examine the specific political opportunity structure of the Netherlands, where pro-nuclear environmentalism was an open niche. In this way, we weigh the importance of the party's pan-European appeal and the country-specific political opportunity structure. We show the importance of the country-specific factors for new party support and thus cast doubt on the ability of pan-European parties to mobilize voters all over Europe with the same message.