Prime Minister Erna Solberg, has claimed victory in a close election.  
With 95 percent of the votes counted on Monday, Solberg's Conservatives, along with their anti-immigration junior coalition partner, the Progress Party, and two other centre-right allies, were projected to win 89 seats in the 169-seat parliament, according a forecast by Norway's Election Directorate. 
The opposition, headed by Labour leader Jonas Gahr Store, was set to win the remaining 80 seats. 
Solberg claimed victory after the latest projection, saying voters had given her a "mandate for four more years". 
The election had been labelled the "biggest election thriller in many decades" by national media.
Labour's Store conceded defeat and wished his rival well. 
"This is a big disappointment for Labour," he told supporters after results showed his party would lose six seats 
Before the election, opinion polls indicated a close race, with an aggregate suggesting just one seat may separate the parties.
Erna said our goal was to give Norway a new government. We knew it was going to be close, and it was close. But as it looks now it wasn't enough to replace a Conservative-Progress Party government with a Labour government.
Solberg's Conservatives meanwhile lost seven seats.
The election outcome hinged in great part on whether Solberg's small centre-right allies, the Liberals and Christian Democrats, would manage to break a key threshold in the vote.
Taking more than four percent of ballots translates into extra seats in parliament. Both parties long hovered around that mark, but were seen surpassing it.
The results confirmed opinion polls which had predicted an extraordinarily close race in "the world's happiest country".
Solberg's re-election marks the first time in more than 30 years a Conservative prime minister has won a second straight term.