SARAJEVO, October 7 , 2018 (Reuters) - Bosnians go to the polls on Sunday to decide whether their country will pursue a path towards European Union membership and NATO integration or sink deeper into ethnic strife and further fragmentation. More than two decades after a war in which 100,000 died, leading Serb, Croat and Muslim Bosniak parties are campaigning on nationalist tickets, reviving wartime pledges in programmes that fail to offer any clear economic or political visions. About 3.35 million registered voters will take part in the presidential and parliamentary elections, choosing members of Bosnia's tripartite inter-ethnic presidency, consisting of a Bosniak, a Croat and a Serb, and lawmakers for parliament's lower house. They will also select leaders and assemblies of its two autonomous regions - the Serb Republic and the Bosniak-Croat Federation, and of the Federation's 10 cantons. In the run-up to the vote, ethnic leaders spread fear using divisive rhetoric reminiscent of the war. Campaigning has been marked by an unprecedented spate of violations, abuse of public funds and hate speech, monitors said. Polling stations opened at 7 a.m. (0500 GMT) and will close at 7 p.m. (1700 GMT), with the first preliminary results expected at midnight. "I don't have any hopes it will be better," said Remzija, who declined to give her surname, after casting her ballot in Sarajevo. "So many years have passed, we were expecting it will be better but it seems it has only got worse," a 65-year-old pensioner said. Nearly 7,500 candidates are running for 518 offices in a country of 3.5 million, reflecting a massive and complex government structure based on ethnic quotas, designed under a peace deal that ended the country's 1992-95 war. Experts say Bosnia cannot progress with such a large administration, but any attempts to change the constitution — an integral part of the U.S.-brokered Dayton peace accords — have been obstructed by Bosnia's rival ethnic groups. The ruling nationalist parties want to preserve the system of patronage under which an estimated 1 million of their party affiliates are employed at different layers of government, cementing electoral loyalties. Such politics have driven about 170,000 educated people out of the country over the past five years, draining Bosnia of its young and threatening the economy.