Croats cast their votes earlier on Sunday to elect a new 160-seat parliament.
Al Jazeera's Jayne Azzopardi said that neither side is likely to gain a full majority.
"It has been a tight race from the very beginning. And as people in Croatia cast their votes they were looking to the future, choosing a leader they hope will revive the economy, fight corruption, tackle poverty and take the county into the European Union," she said.
Voters have been frustrated by their standard of living, although Ivo Sanader, the prime minister and leader of the HDZ, claims his government has boosted growth and created jobs.
"For me personally elections present a celebration of democracy and our citizens must decide how they will live in Croatia in the next four years," Sanader said.
Zoran Milanovic, his Social Democrat challenger, also promises to beat corruption and fight unemployment, but has different ideas about how to go about it.
"A new course, a new turn of politics. A new face of politics - not just polished, brushed up on the billboard, but new content. That is what it is all about. This country has been way too tired of corruption and all other malformation stuff. So its time to turn. A u-turn," Milanovic said.