The opposition Labour Party, led by Viktor Uspaskich, once dubbed the “pickle king” for having made his fortune selling jarred pickles, was leading with 23.4 per cent of the vote after nearly three-quarters of precincts were counted.
The victory set the stage for a coalition with the Social Democrats, who were second with 19.4 per cent, and Order and Justice in fourth with 9.2 per cent.
The current conservative ruling coalition, led by prime minister Andrius Kubilius, finished third with 12.3 per cent of the vote.
The Labour Party victory would signify a tremendous comeback for Mr Uspaskich, a member of the European Parliament still under investigation in Lithuania for allegedly fraudulent party finance operations.
In 2006 he was forced to resign as economy minister for a conflict of interest case with Russia and suspicions about a faked diploma from a Moscow-based institute.