Swedes voted in legislative elections on Sunday that will either pave the way for an unprecedented right-wing government supported by the far right or a third straight mandate for the ruling Social Democrats.
Opinion polls have predicted a close race with a razor-thin lead for Prime Minister Magdalena Andersson's Social Democrats and the left bloc, following a campaign dominated by rising gang shootings and soaring electricity prices.
Polling stations were to close at 1800 GMT, with final results due around midnight.
At a voting station set up in Stockholm's Central Station, 34-year-old IT worker Erwin Marklund said he was concerned about the rise of the far right and had voted for the small Left Party.
"It's important to not get the far right into the system," he told AFP.
The right-wing bloc has never before agreed to cooperate with the nationalist and anti-immigration Sweden Democrats, long treated as "pariahs" by other political parties.
The far right has leapt to second place in opinion polls behind the Social Democrats in the final weeks of the campaign, credited with around a fifth of votes.
Their surge -- overtaking the traditional leaders of the right-wing bloc, the conservative Moderates -- was attributed to an election race focused on issues close to their voters, including crime, segregation and the integration of immigrants.
Prime Minister Andersson, 55, hopes however to hang onto power with the support of the small Left, Centre and Green parties.
"It's going to be very, very close", she told reporters as she cast her ballot in the Stockholm suburb of Nacka on Sunday.
Andersson, whose party has dominated Swedish politics since the 1930s, enjoys broad support among Swedes.
She has consistently led her challenger for the post of prime minister, Moderates leader Ulf Kristersson, by a wide margin in opinion polls.
Yet pollsters put the two blocs in an almost dead heat, predicting 49.7% to 51.6% of voter support for the left and 47.6% to 49.4% for the right.
While online betting sites meanwhile gave Andersson as the favorite, Kristersson said on Sunday that he felt confident.
"It feels like we have a lot of support and wind in our sails," he said as he cast his ballot.
Kristersson is the architect behind a major U-turn for the right wing.
He launched exploratory talks with the Sweden Democrats in 2019 and deepened their cooperation before the two other small right-wing parties, the Christian Democrats and to a lesser extent the Liberals, followed suit.
Sweden Democrats' leader Jimmie Akesson told reporters as he queued to vote in Stockholm that "we hope to be in the government" and his first priority would be to "push back crime."