* Kosovo votes under shadow of war crimes investigation
* Thaci bidding for third term as prime minister
* Voters angry over poverty, corruption (Updates with exit poll)
By Fatos Bytyci and Matt Robinson
PRISTINA, June 8 (Reuters) - An exit poll put Kosovo's ruling party of Prime Minister Hashim Thaci narrowly ahead in an election on Sunday marked by a low turnout among Kosovars frustrated with widespread poverty and corruption.
Preliminary official results were expected later in the evening, but the exit poll conducted by the Gani Bobi social research institute put Thaci's Democratic Party of Kosovo (PDK) on 33 percent, just ahead of the opposition Democratic League of Kosovo (LDK) on 30 percent. The poll has a 2 percent margin of error.
Analysts had long predicted the closest race since 46-year-old Thaci presided over Kosovo's Western-backed declaration of independence in 2008.
Frustration with Kosovo's progress is running high among many of its 1.8 million people, who rank among Europe's poorest. A third of the workforce is unemployed. Corruption is rife.
Turnout was around 43 percent, down on the past two elections in 2007 and 2010, when 54 percent and 48 percent of eligible voters cast their ballots.
Voting appeared to be slow among ethnic Serbs in a pocket of northern Kosovo that the European Union is trying to integrate in agreement with Serbia.
If he wins, Thaci will come under immediate pressure from the West to heed the findings of a war crimes investigation that threatens to ensnare his former comrades-in-arms.
"This old class of politician has been around for 15 years and had plenty of time to profit," said Muhamet Maqastena, a trader in the capital, Pristina. "It's time for them to go and let the young, educated people govern us."
Valbona Bajraktari, a 37-year-old unemployed woman, said her expectations were not high. "The only thing I want is for them not to steal or to hire their aunts," she told Reuters.
Fighting back, Thaci's government raised public sector wages, pensions and social welfare benefits two months ago by 25 percent. That directly affects 240,000 teachers, doctors, police officers, pensioners and others, and even more indirectly.
He has promised to do the same every year if given a new four-year mandate. (Editing by David Goodman)