The opposition liberal Reform party is on track to win Estonia's general election, garnering nearly a 10 percent lead over the center-left Centre Party of Prime Minister Juri Ratas, partial results show.
According to results from more than 80 percent of polling stations, the center-right pro-West Reform Party captured 30.3 percent of the vote, followed by the Centre Party, which took 20.9 percent, the official state elections website said.
The nationalist, far-right Estonian Conservative People's Party, also known as EKRE, was running third with 17.5 percent.
Two parties in the governing coalition, the Social Democrats and Isamaa, took 10.2 percent and 11.7 percent of the vote, respectively.
Nearly 1 million people were eligible to vote in the former Soviet republic of some 1.32 million people, with 101 parliament seats up for grabs.
Election officials said voter turnout was nearly 60 percent four hours before polls closed. About one-quarter of eligible voters had already cast their votes online.
The Center Party has supporters among the ethnic Russians who make up 25 percent of the population.
In 2016, Ratas took over as party leader and established a three-party coalition government that took office in November 2016.
The Center Party signed a memorandum of understanding with Russian President Vladimir Putin's United Russia party in 2004. Ratas has said the deal is "frozen," but he has refused to rip it up.
Russia has kept close watch on the military and security affairs of Estonia and Baltic neighbors Latvia and Lithuania since they became NATO members in 2004, just 13 years after breaking free from the collapsing U.S.S.R.
The United States never recognized the Baltic states as Soviet republics.
NATO placed a multinational battalion in Estonia in 2017 as it beefed up its presence near Russia's borders after the Baltic state expressed concerns over Moscow's annexation of Crimea from Ukraine in 2014.
Estonia has seen several high-profile spy cases involving Russia since its 1991 independence.