TORONTO — As several thousand ballots were cast to elect Ontario's next Liberal leader, tens of thousands of protesters clamoured outside the convention Saturday eager to send the newly crowned premier a message.

Those protesters, largely teachers supported by workers from a number of sectors of organized labour, crowded outside Toronto's Maple Leaf Gardens.

They marched, sang and chanted protesting Bill 115, which imposed collective bargaining agreements on public school teachers earlier this month before being repealed last week.

"You cannot just trample democratic rights in this province and think things will be back to normal when you repeal the bill that did that,” said Elementary Teachers' Federation of Ontario president Sam Hammond.

Hammond said the boisterous crowd drew support form across the province. Officials with the union said 121 buses from across Ontario converged just blocks from the old hockey arena to kick off the rally with a series of speeches.

"Our sisters and brothers from the labour movement are here with us," Hammond said. "There are people here from Moosonee, from Fort Frances, protesting today from other unions to make the statement we want to make."

After the province's labour board ruled teachers' planned one-day strikes were illegal, union leaders decided the leadership convention would be the best venue to voice their displeasure with Bill 115, Hammond said.

Sid Ryan, president of the Ontario Federation of Labour, told the crowd the Liberal austerity measures have not only hurt teachers, but everyone across the province.