Sweden woke Monday to the prospect of weeks of political uncertainty after the country's two rival blocs failed to secure a clear governing majority in elections that saw a boost for a far-right party amid growing discontent with large-scale immigration.

The governing center-left bloc had a razor-thin edge over the center-right opposition Alliance. With nearly all votes counted on Monday, the ruling center-left Social Democrats and Greens and their Left Party parliamentary ally had 40.6 percent of the vote, while the opposition centre-right Alliance was on 40.3 percent.

However, both have vowed not to work with the Sweden Democrats, an anti-immigrant party with roots in a neo-Nazi movement.

The Sweden Democrats came third with 17.6 percent, about 5 percentage points more than four years ago. The result was largely in line with the conventional opinion polls but below the 20 percent or more figure that some surveys had predicted.

"Most pointed towards the Sweden Democrats taking over the position as the second-biggest party in Sweden. But the expected ... bang did not happen," the liberal Expressen daily said in an op-ed piece.

"We need to be sincerely grateful for that. Sweden is now on steadier grounds than what we could have feared before the election."

But while there was a sense of relief among supporters of mainstream parties about the nationalist group's more limited than expected gains, the election underscored a broader shift to the right in one of Europe's most socially progressive nations.

Their success follow a rise in popularity for other far-right parties in Europe amid growing anxiety over national identity, the effects of globalization and fears over immigration boosted partly by conflicts in the Middle East and North Africa.

Prime Minister Stefan Lofven, who brought the Social Democrats to power in 2014, said he intended to remain in the job. The center-left party emerged with the greatest share of the vote — 28.4 percent as the count neared completion — yet looking at holding fewer parliament seats than four years ago.

The leader of the Moderates party that came in second, Ulf Kristersson, has already called on Lofven to resign and claimed the right to form Sweden's next government.

The center-right, four-party Alliance has said it would meet Monday to discuss how to move forward and demand that Lofven, head of the minority, two-party governing coalition, resign.

Final election returns were expected later in the week. The preliminary results made it unlikely any party would secure a majority of 175 seats in the 349-seat Riksdag, Sweden's parliament.

With the prospect of weeks or months of coalition talks before the next government is formed, Swedish tabloid Expressen headlined its front page Monday: "Chaos."

Both the left-leaning bloc led by the Social Democrats and the center-right bloc in which the Moderates is the largest of four parties have said they would refuse to consider the Sweden Democrats as a coalition partner.

Lofven told his supporters the election presented "a situation that all responsible parties must deal with," adding that "a party with roots in Nazism" would "never ever offer anything responsible, but hatred."

"We have a moral responsibility. We must gather all forces for good. We won't mourn, we will organize ourselves," he said.

Sweden — home to the Nobel prizes and militarily neutral for the better part of two centuries — has been known for its comparatively open doors to migrants and refugees. Sunday's general election was the first since Sweden, which a population of 10 million, took in a record 163,000 refugees in 2015 — the highest per capita of any European country.

Turnout in the election was reported at 84.4 percent, up from 83 percent in 2014.