After votes in all 40 electoral districts have been calculated, the preliminary results show that Haase got 60.89 percent of votes, and her rival, independent candidate Mindaugas Bastys received 35.47 percent of votes.
Voter turnout was 27.08 percent, or 8 413 voters, despite 31 062 people being registered on the local electoral roll.
The by-election in Zanavykai constituency was held after its representative in the parliament, Bastys, renounced his mandate following a failed impeachment and a large protest outside the parliament.
The Constitutional Court earlier ruled that Bastys had breached his oath and committed a gross violation of the Constitution after he hid his ties with a former KGB agent.