The birth of this country’s largest private-sector union got another step closer Monday, after the Communications, Energy and Paperworkers Union of Canada voted overwhelmingly in favour of a merger with the Canadian Auto Workers.

CEP president Dave Coles told reporters Monday that more than 90 per cent of the union’s members endorsed the merger.

“This just isn’t a step forward for the labour movement, it’s actually a step forward for progressive people in this country,” Coles said.

“It sends a message to the Conservatives and any other political group that thinks that they can attack workers: an attack against one will be a response from all of us.”

The CAW gave its go-ahead for the merger in August.

CAW secretary-treasurer Peter Kennedy said he was “thrilled with the results of the vote.”

But he also said there is a lot of work ahead before it’s possible “to consummate this marriage of two hell-raisers.”

Kennedy said CEP and CAW leaders will next form working groups that will draft a constitution and founding documents for the new union, among other tasks. A convention in 2013 will officially bring the two unions together “with a new name, a new identity and a new purpose.”

The new union will start with more than 300,000 members. Coles said the plan is to devote 10 per cent of revenues to adding new members, and predicts the union could double in size “in a very short period of time.”

The new union would be open to students, retirees and the unemployed, Coles said.

"We want to have everyone in society have the right for a collective voice."

It was unclear Monday if Coles or CAW president Ken Lewenza plan to seek the new union’s leadership.

Both men said their aim is to counter moves by the federal government to wade into labour disputes, most recently at Canada Post and Air Canada.

Both said the new union will offer strong representation of a “progressive” agenda in Canada.

"To the Canadian population outside of the labour movement, we are the vision for a better Canada, we are a vision that is going to be inclusive, we are a vision that's going to make space quite frankly for those that have no voice,” Lewenza said.

Labour expert Pradeep Kumar of Queen’s University said the new union will likely be very politically active.

"I don't think it necessarily means more strikes, but what it means really is there could be more political campaigning on the part of the unions against legislation," Kumar told The Canadian Press.

With files from The Canadian Press