TORONTO- Despite being plagued by scandals, a $25-billion deficit and an unpopular plan to harmonize sales taxes, Premier Dalton McGuinty ostensibly put the Liberal government's record on the line Wednesday and called a byelection to replace former deputy premier George Smitherman.

While byelections are hailed by opposition parties as a chance for voters to voice their discontent with the government, opposition insiders concede they are unlikely to defeat the Liberals Feb. 4 in Toronto Centre. Smitherman held the riding for the past decade until he stepped down to take a run at the mayor's chair in Toronto.

McGuinty moved with the political equivalent of light speed to call the byelection following Smitherman's resignation as a member of provincial parliament last weekend, using the very first legal opportunity to schedule the vote.

Under Ontario's Election Act, elections must be called on a Wednesday and held the fifth Thursday after the date of the issue of the writ.

McGuinty has never moved so quickly to fill a vacant seat in the legislature, especially during the two years when former Progressive Conservative leader John Tory was seeking a riding in which to run after losing his seat in the 2007 election.

The premier called the byelection on the very day the Liberals were scheduled to formally nominate former Winnipeg mayor Glen Murray as their candidate in the downtown Toronto riding.

Working on climate change initiatives, pushing for more public transit and fighting for affordable housing to help end homelessness makes him a good fit with the Liberal government and its dedication to a greener environment and economy, said Murray.

"I live in Toronto Centre because it is a connected, walkable, dense transit-friendly community," he said in an interview.

"It's the way that a lot of us in Canada will have to start living. This is the world in a constituency."

Murray is supported by Smitherman and the Liberal establishment, and is already considered potential cabinet material with his background as a community activist and a government leader.

"He had time as a leader in Winnipeg and has lived in Toronto for over five years now, and has continued to be involved in delivering results through the premier's climate change panel and other things like that," said one senior Liberal. "He does bring a specific skill set."

McGuinty is expected to shuffle his cabinet before the legislature resumes sitting in mid-February, and if he delays until after the byelection it could be a sign Murray will immediately be promoted to the front benches if he holds Toronto Centre.

Well-known street nurse and public housing activist Cathy Crowe will run for the New Democrats.

"Toronto Centre voters have a chance in this byelection to send a new community voice to Queen's Park and send an arrogant and out-of-touch McGuinty government a strong message," said NDP Leader Andrea Horwath.

The Progressive Conservatives plan to nominate their candidate next week, but so far the only name being mentioned publicly was Pam Taylor, who ran for the party against Smitherman in the 2007 general election.

The Green Party of Ontario, which has never won a seat in the legislature, said it had at least one candidate ready to run and others could come forward before the nomination meeting this Sunday.

"We for sure will have a candidate and we may have a contested nomination, but we don't know yet," said Green Ontario Leader Mike Schreiner.

"We see this as an opportunity to get our message out, and a great opportunity to build capacity in our party."