TORONTO - The race may be on to find a new leader, but the Ontario's New Democrats will have to crown a successor who will appeal to vote-rich Toronto and southern Ontario if it wants to gain more ground ahead of the next provincial election in 2011, experts say.

It also needs to build on what departing leader Howard Hampton started -- returning the party to its roots as the voice of the working class and winning back the labour movement as its traditional base of support.

Hampton will be leaving next year after nearly 13 years at the job, having seen the party through three provincial elections but failing to have made any significant gains in popular support or the number of seats in the legislature.

Yet the timing's never been better to score points against the governing Liberals and Premier Dalton McGuinty, who are grappling with dire predictions of a recession and mounting job losses in the troubled manufacturing sector.

Canadian Auto Workers president Buzz Hargrove may back the Liberals, but Hampton's recent trips to Oshawa to support workers livid over General Motors' plans to close a truck assembly plant has put the NDP back on the map, said Henry Jacek, a political science professor at McMaster University in Hamilton.

"He's been making a very strong appeal to the rank-and-file auto workers that he's their defender and that the McGuinty government has not really forced GM to live up its responsibilities in the province,'' he said.

Hampton, who triggered the leadership race Saturday by announcing he'd step down next March, urged the party to remain true to the legacy left by former leaders Donald MacDonald and Stephen Lewis _ reaching out to "ordinary folks'' while forging an alliance with the labour movement, the ''biggest force for equality'' in the province.

"It is time for New Democrats to think again about where we want to position ourselves and how we want to raise the issues that matter to so many people across this province -- issues that otherwise wouldn't be raised,'' he told the party faithful.

One of the biggest challenges on the labour front will be winning over teachers and other prominent groups who are growing disenchanted with the Liberals, Jacek said. The other will be finding a leader who can broaden their support across the province.

"They have the north pretty well solidified, and they've had Howard Hampton representing the north,'' he said.

"I think there's going to be a lot of people in the party here going to say, `What we really have to do is come down and pick somebody who is extremely popular in southern Ontario, particularly Toronto.''

The ''dream candidate'' for many is left-leaning Toronto Mayor David Miller, although a federal MP could also end up seeking the top job, Jacek added.

Having a strong Toronto leader could give the NDP a big advantage, since McGuinty hails from Ottawa and Progressive Conservative Leader John Tory was shut out of a Toronto riding in the last election, he said.

"If they can just increase their appeal a little bit more, they can get started having some of those seats in metro Toronto and Oshawa and some other places start to fall into their lap,'' Jacek said.

"They've been partially cultivated because, in a lot of those areas, the manufacturing jobs have gone. So Howard Hampton has tried to cultivate those people and that needs to continue.''

While no one's officially thrown their hat into the ring, three Toronto caucus members are rumoured to be interested in the job: Peter Tabuns, Cheri DiNovo and Michael Prue. Former provincial politician Marilyn Churley, who held a Toronto riding, is also considered to be a potential candidate.

Tabuns, a former city councillor and executive director of Greenpeace, failed to win a federal seat in 2004 but is widely expected to come forward as a candidate to replace Hampton.

DiNovo, a feisty United Church minister, assumed office over a year ago but has already made a name for herself by championing social justice causes, including raising the minimum wage.

Prue has frequently pressed for better conditions for the province's poorest residents, even going so far as to try and live on a $12.75-a-week "welfare diet'' in 2002 to bring attention to those living in poverty under the previous Conservative government.

Most caucus members refused to speculate on possible leadership hopes Saturday, saying the weekend was about paying tribute to Hampton.

However, the leadership race was a hot topic of discussion among Liberal cabinet ministers, backbenchers and delegates attending the party's annual general meeting in Ottawa this weekend. Several possible candidates were talked about and appraised, with DiNovo's name coming up most often, and not always in a supportive way. 

Rather than divide the NDP caucus, a ''robust'' leadership is exactly what the party needs to get its message out to voters, Hampton said.

''You do some work in the legislature as a leadership candidate, and then you do a lot of work out there in community after community, raising the issues,'' he said. ''So this will actually, I think, raise our productivity.''

Hampton should be given credit for keeping the party alive when many had pronounced it dead -- once when it lost official party status after the 1999 election, and again in 2003, said Jacek.

The NDP has since recovered from the tumultuous years of former NDP premier Bob Rae, whose government alienated the party's tradition labour support base in 1993 with its Social Contract -- a series of austerity measures which included so-called ''Rae days'' that forced government workers to take unpaid days off.

Hampton, who was tainted by his years in Rae's cabinet, managed to put the party back on track, said Jacek. But there's still a long way to go.

"They have to go back to what was working for them,'' he said. "They have to go back to the formula that Donald MacDonald, Stephen Lewis had. That was the formula that worked.''