Thomas Mulcair wins final vote to become leader of the NDP
5:30 p.m. EST -- A deliberate attempt to hack the NDP's online voting system failed to compromise any votes but forced the NDP to delay voting, said NDP principle secretary Brad Lavigne.
Lavigne compared the situation to a robber trying to break into a home but being scared away by the alarm system.
The NDP's voting system is run by a Spanish company. The alleged hackers filled up the space reserved for NDP members to vote, slowing down the system and setting off alarms.
Lavigne stressed that the alleged hackers did not get into the system or compromise the process.
"The vote is very, very safe," said Lavigne.
Meanwhile, supporters of Brian Topp, Thomas Mulcair and Nathan Cullen returned to the convention hall singing, banging drums, hoisting dozens of signs and cheering the names of their candidates.
Organizers have said they will release the results of the third round of voting at 6:00 p.m. EST.
Lavigne did not say whether or not any members were unable to vote at all because of the delay.
He said they are working with the Spanish company running the voting system to find out exactly what had happened.
4:30 p.m. EST -- NDP members trying to vote in the third round of balloting overloaded the party's website and forced it to extend voting, said NDP President Rebecca Blaikie.
The party's priority is to make sure every member has the chance to vote, Blaikie said from the convention stage.
Journalists swarmed Brad Lavigne, principle secretary to the NDP's leader, asking how the party could not have foreseen the situation.
"We couldn't handle the volume, a lot of folks were coming through at the same time," Lavigne said.
Or is it?
Three candidates remain in the third round: Cullen, Topp and Mulcair.
Peggy Nash dropped out of the race after finishing fourth in the second round of voting with 10,519 votes. Mulcair was first again with 23,902 votes.
Topp scored 15,624 and Cullen 12,449.
Nathan Cullen is the underdog going up against frontrunners Brian Topp and Thomas Mulcair
In the minutes after the results were announced Topp and Mulcair supporters swarmed Nash's camp trying to win as many of them over to their candidate as they could.
One Mulcair supporter shouted out, "We need someone who can start work on Monday! Come on Thomas!" as Nash supporters filed past.
Topp told reporters it's still anybody's race.
"You don't know anything in a convention, you just have to see," said Topp. "That's one of the reasons why these things are so much fun."
Topp said his campaign was calling NDP members and sending out emails to shore up support for the third round.
Stewart Wise, a mechanic and member of the Canadian Auto Workers' Union, sat alone on a riser wearing a purple wig. He was a Nash supporter.
"I'm a little sad that Peggy didn't win," he said. Now he's a Topp supporter. He's following the lead of Sid Ryan, president of the Ontario Federation of Labour.
Organizers said results of the third vote will be released at 6:00 p.m. But with questions mounting about how and why the website failed, and an expected fourth round of balloting, the evening may last a little longer than many expected.
4:00 p.m. EST -- NDP President Rebecca Blaikie just made an announcement to the convention: because of "technical difficulties" voting will be closed to NDP members outside of the convention for the next 30 minutes so all members inside the convention can vote.
Then, at 4:40 p.m. voting will be closed in the convention and re-opened to members outside. They will be able to vote from 4:40 p.m. to 5:50 p.m.
2:15 p.m. EST -- Even though Mulcair is leading, there is already a minor backlash on social media, with some NDP members saying he is too conservative.