The four NDP leadership candidates remaining in the race were busy lining up new support as they waited for the results of the second ballot.
Thomas Mulcair, who placed first in the initial round of voting, secured the support of MP Charlie Angus, who switched over after Paul Dewar dropped out. As expected, Mulcair also picked up Martin Singh after he dropped out the race.
Fourth after round one of voting, Peggy Nash picked up the backing of Christine Moore, the MP for Abitibi-Temiscamingue, and Rathika Sitsabaiesen, MP for Scarborough--Rouge River.
Second-place finisher Brian Topp and third-place finisher Nathan Cullen remain in the race as well. Cullen picked up the support of Western Arctic MP Dennis Bevington.
Voting in the second round was extended by 30 minutes to 12:45 p.m. ET due to delays in online voting.
There were some reports on Twitter of online voting problems during the second round, with people saying they were unable to load the voting page.
An NDP official said the site was slow due to high traffic, and urged members to keep trying to get into the site.
In the first round, Thomas Mulcair garnered more than 30 per cent of the vote, which also saw Niki Ashton eliminated and Paul Dewar and Martin Singh drop out.
Nathan Cullen finished a surprising third at 16.4 per cent, followed by Peggy Nash, who earned 12.8 per cent of the vote.
Mulcair camp erupts
At the release of the first ballot results, Mulcair and his supporters erupted with excitement, his wife jumping to her feet. Mulcair hugged and exchanged high fives with supporters around him.
"We're ecstatic," Mulcair said, giving a thumbs up.
"We're just going to keep talking, keep working," Mulcair said.
"Thirty per cent was my magic number," said former MP Lorne Nystrom, who is Mulcair's campaign co-chair. Nystrom said he was happy with the lead over Topp.
Shortly after the results were released, Singh, who finished second last in first round of voting, walked over to throw his support behind Mulcair.
Singh said Mulcair is the best person to move the ideas from his own platform forward.
"The next best candidate was Thomas Mulcair," Singh said.
Nash said she had not given thought to dropping after the first rounding of voting.
"I'm not unhappy with the results," said Nash. "I think that I've got a lot of second- and third-ballot support."
Ontario Federation of Labour president Sid Ryan, a Nash supporter, slammed Mulcair as not having respect for the labour movement and he asked Nash to throw her backing behind Brian Topp.
Dewar releases supporters
Dewar, an Ottawa area MP, also dropped out after he got 7.5 per cent support. He did not endorse another candidate.
"There comes a time when you have to make a decision. I'm making that decision. I am dropping out of the race. I am not going to any other candidate," Dewar said.
MP Charlie Angus, who was a Dewar supporter, immediately threw his support behind Mulcair.
"Thomas is fearless, Thomas is organized," said Angus, adding that he's developed a great support base across the country. "He's one of the strongest MP's we've seen in the House of Commons and he's certainly a match for Stephen Harper."
"I thought Paul Dewar has what it takes," said Angus, "and Thomas Mulcair has what it takes."
However, it wasn't a clear decision for some of Dewar's other backers, who expressed shock and disappointment at the results.
"I didn't have a Number Two," said Mary Sanderson, standing in front of Dewar's bleacher section at the convention.
"I think [Dewar has] gained a lot of experience so I could see him running in the future," said Vivian Wylie.
Dennis Bevington, the MP for Western Arctic and originally a Dewar supporter, threw his support behind Cullen.
"He represents really the new thinking in the party," Bevington said about his new choice. Cullen understands issues important to northern Canada, he said
"We've got a real horse race going here and it's going to be one that I hope people are watching closely," Bevington added.
As one candidate did not get more than 50 per cent of the vote, the race is going to a second ballot.
Two names were automatically dropped from the list of candidates: that of Romeo Saganash, who had been the eighth candidate in the race but dropped out after the ballots were prepared, and Niki Ashton who received the lowest number of votes in the first round.
Ashton got 5.7 per cent support on the first ballot and released her supporters without endorsing another candidates.
There will be about 90 minutes between rounds for voters to cast their ballots.
More than 55,000 of 131,000 eligible members voted in advance and about 4,200 members are registered at the convention.
With files from The Canadian Press