The referendum on electoral reform was too close to call early Wednesday morning, with about 57 per cent voting Yes and 43 per cent voting No.

Elections B.C. officials told CBC News that complete results will be late in coming, but the last count on election night pointed to the Yes side coming up just short of the threshold needed to pass the measure.

For the referendum to pass, the Yes side needs 60 per cent of all ballots cast, as well as a majority in 60 per cent of the ridings – the so-called 60/60 formula.

The single transferable vote system, known as BC-STV, would change how votes are counted. If passed, British Columbia would be North America's first large jurisdiction to bring in proportional representation.

As voters entered polling stations Tuesday they were given two ballots: one listing the candidates running for the legislature, and a second Yes/No ballot for the referendum.

Under the BC-STV system, a candidate would have had to win only a certain number of votes in order to be guaranteed a seat in the legislature. Districts would likely elect three or more candidates who reached that threshold.

Under the current system, voters mark only one choice on the ballot. Under the proposed system, voters would choose their favoured candidates from the list of those running, and number them in order of preference.

As the ballots are counted, a vote cast for someone already declared elected would be transferred to the voters' next choice. The vote transfer continues until the proper number of candidates is declared elected. Likewise, votes for someone who has no hope of winning are transferred to a candidate still in the running.

In its report recommending the new system, the Citizens' Assembly on Electoral Reform said that by transferring a portion of the vote away from a candidate who is either already elected or has been defeated, the vote would not be "wasted." Also, candidates from newer parties stand a better chance of winning a seat.

The non-partisan committee was set up by the provincial government after the 2001 general election.

Opponents of the system claimed that it could result in more coalition or minority governments and greater instability.