The last stage of B.C.'s 40th general election is underway with the start of the final vote count — and there is the potential for election night results to be overturned.

There are nearly 180,000 absentee and mail-in ballots yet to be included in the final tally. (CBC)

Six ridings saw close races, where fewer than 500 votes separate the front runners, and there are nearly 180,000 absentee and mail-in ballots yet to be included in the final tally.

In Saanich North and the Islands, the NDP beat the Liberals by just 52 votes, and the Green Party came in third by just 335 votes.

Elections B.C. spokesman Don Main says because of the tight three-way race, officials will delay the final vote count until the election night numbers get a second look.

"In Saanich North and the Islands, there's a recount taking place first of the initial count and then that district electoral officer will go onto the final count process."

While Elections B.C. won't confirm the numbers, the parties say there are as many as 2,500 absentee ballots in the riding that haven't yet been counted.

Final counting will continue over the next three days.