STEPHEN Harper has been re-elected Canada's prime minister

STEPHEN Harper has been re-elected Canada's prime minister at the head of a majority Conservative government, television projections say.

Canadian voters delivered Harper his first majority government after five years of governing in a minority situation, CBC News said today.

Meanwhile New Democrats (NDP) Leader Jack Layton was set to become official opposition leader.

As of 10.49pm eastern Canadian time (12.49pm AEST today), the Conservatives were elected or leading in 164 seats, followed by the NDP with 103, Liberals with 32 and the Bloc Quebecois with four, CBC reported.

A party needs to capture 155 seats to win a majority in the House of Commons, according to CBC.

The NDP, according to projections, made a major breakthrough and appeared to have nearly tripled its seat count, while the Liberals were poised to suffer a stunning historic electoral loss and place third.

Mr Harper, who took office in 2006, has won two elections but until now had never held a majority of parliament's 308 seats, forcing him to rely on the opposition to pass legislation.