Rosen Plevneliev, presidential candidate of Bulgaria's centre-right ruling GERB party casts his vote at a polling station in Sofia October 23, 2011. Plevneliev is set to lead in the first round of Bulgaria's presidential election on Sunday, but will probably need a run-off to secure the position after a campaign marred by protests and violence. REUTERS/Stoyan Nenov (BULGARIA - Tags: ELECTIONS POLITICS)