TORONTO -- Ontario's Progressive Conservatives have extended a registration deadline by one day for those wanting to vote for a new leader, but some candidates in the race want party members to be given even more time.

Registration was to end Wednesday night, but the chairman of the leadership organizing committee tweeted Wednesday afternoon that the deadline was extended to 8 p.m. on Thursday.

Hartley Lefton said the verification process is being extended due to a "continued stream" of members seeking verification PINs, adding that by mid-afternoon more than 40,000 party members had cast ballots in the race.

Some of the four candidates vying to take the party reins have criticized the complexity of the voting system, which was launched after former leader Patrick Brown abruptly resigned in January amid sexual misconduct allegations.

Brown, who vehemently denies the allegations, briefly tried to reclaim his old job, but bowed out of the race last week, saying his bid was taking a toll on family and friends.

Former provincial legislator Christine Elliott, former Toronto city councillor Doug Ford, Toronto lawyer and business woman Caroline Mulroney and social conservative advocate Tanya Granic Allen are the four candidates competing for the top job.

The Tories, whose membership management system was hacked in November, implemented a two-step process to verify the identity of voters that requires party members to submit photo identification and wait to receive a special code in the mail.

Ford, who said he has met many "outraged" voters who have not received their verification packages -- called on the party to extend both the verification and voting periods by one week.

"While we understand that the party is proud of the number of people that have voted thus far, we charge that the very substantial number of people that have been shut out of voting in this leadership makes this number immaterial," Ford said in a statement.

"When thousands of people who have paid for memberships in order to vote for the next leader of the Ontario PC party do not get to participate because they are not sent verification packages, there is a big problem."

Mulroney said she also has heard from members who have not received their packages and, thus, cannot vote.

"This proposal to extend registration and voting is the right thing for democracy and for our party -- I support it," she said.

Voting is to end at noon on Friday and the results of the leadership contest are still slated to be revealed Saturday, which will give the new leader about three months until the provincial election.

The leadership will be determined using a ranked ballot, in which voters pick their preferred candidates and have the option to select a second, third and fourth choice.

The winner is whoever receives more than half the total electoral votes.

If no one crosses that threshold on the first round, whoever has the fewest votes or less than 10 per cent gets eliminated and those votes get redistributed to whoever was marked as the second choice. This continues until a winner emerges.