Bosnians voted on Sunday in municipal elections marked by a battle in the Bosnian Serb half of the country between a pro-European Union coalition and the pro-Russia separatist party that has ruled that region for more than a decade. Some 3 million voters will choose mayors and municipal councils in both of Bosnia's two semi-autonomous regions. Those areas — the Republika Srpska and the Bosniak-Croat Federation — have their own governments, presidents and parliaments, but are linked by shared federal-level institutions. In Republika Srpska, the ruling Alliance of Independent Social-Democrats campaigned on a promise of Serb secession from Bosnia — something many nationalist Serbs have been seeking since Yugoslavia collapsed during the 1990s. The party is led by President Milorad Dodik, who has dominated the Bosnian Serb political scene for years but now faces political setbacks. Dodik's opponents — the equally nationalistic Alliance for Changes — see the future Republika Srpska as a semi-autonomous region within a Bosnia that is an EU member. They have focused on bread-and-butter economic issues while accusing Dodik of corruption and of throwing the region into poverty. "If we vote for change, things will get better," said Slavko Maslovaric, a resident of the Republika Srpska capital of Banja Luka. If the same people stay in power "it could get even get worse." Dodik tried to shift voters' attention away from the corruption accusations by holding, a week before this election, a divisive Bosnian Serb referendum over a disputed Republika Srpska holiday that the country's constitutional court had banned because it discriminates against non-Serbs. The court also banned the referendum, but Dodik conducted it anyway. Voters overwhelmingly approved the holiday, although non-Serbs mostly boycotted the vote. The West threatened him with sanctions but he received support from Russia. The state prosecutor issued him a summons for Monday but he said he won't go. Another Banja Luka resident, Biljana Sevo, said this attitude only strengthens Dodik's popularity among Serbs. "I think most people are in favor of him ... I think he will stay in power," she said. Tensions are high. Locals in the Bosnian Serb town of Prnjavor got into a fistfight overnight with young men who arrived from Serbia. Bosnian Security Minister Dragan Mektic told journalists the Serbians were paid by a local tycoon "to cause incidents." Local media identified the businessman as an ally of Dodik's.