Takhar announced his candidacy Thursday night on Facebook, with just hours to go before the 5 p.m. Friday deadline to declare, although he plans a formal campaign launch Saturday in his Mississauga riding.
He is the sixth candidate from the Greater Toronto Area, leaving Sandra Pupatello of Windsor as the only would-be leader from outside the capital.
Pupatello and Gerard Kennedy are the only leadership candidates who are not currently members of the legislature, but both are former McGuinty cabinet ministers.
Pupatello quit in 2011 to work in the private sector, while Kennedy left Ontario politics for the federal scene in 2006, and lost a bid for the national Liberal leadership to Stephane Dion. He also lost his seat in Parliament in the 2011 federal election.
All of the other candidates _ Kathleen Wynne, Glenn Murray, Charles Sousa and Eric Hoskins _ had to follow McGuinty's order to quit the Ontario cabinet before launching their leadership campaigns.
All the leadership hopefuls are in their 50s, except Takhar who is 61, and there hasn't been a lot of policy differences emerging so far, with each candidate careful not to tread too heavily on the Liberal government's record.
Kennedy made a point of saying he doesn't carry the baggage from recent scandals, but the Tories point out he was a key cabinet player when McGuinty broke a written pledge not to raise taxes with a health tax of up to $900 for every Ontario worker.
Murray has talked about giving northern Ontario more autonomy, so Wynne countered with a promise to strike a cabinet committee on the north, while Sousa said he would speed-up development of mining in the Ring of Fire near James Bay.
Kennedy and Wynne have also suggested they would back away from controversial legislation that imposes a two-year wage freeze on most teachers, an issue that has turned a large group of long-time Liberal supporters into angry opponents.
Each of the would-be premiers has been busy signing up new Liberal party members who will be eligible to vote for the delegates who will actually vote directly for the next premier.
Party officials declined to say Friday how many new members had been signed up since McGuinty announced his resignation Oct. 15, triggering the leadership contest. Individual campaigns said they were signing up thousands of new members, but also declined to disclose actual figures.
Unlike most parties that opened leadership votes to all party members and allowed online balloting, Ontario Liberals will select about 2,000 delegates, including 16 from each riding to attend the leadership convention.
Delegates will be selected at local meetings in all 107 ridings the weekend of Jan. 12, with would-be delegates declaring in advance which candidate they support. The leadership convention itself will be held at Maple Leaf Gardens in Toronto Jan. 25-26.
The leadership candidates will square off in a series of debates around the province, beginning Dec. 1 in Ingersoll, followed by Thunder Bay Dec, 9, Ottawa Dec. 18, Ajax Jan. 6 and Toronto on Jan. 9.
The Opposition said the next Liberal leader won't be able to run away from problems that plagued the government, including the $1-billion eHealth scandal, a police probe of the Ornge air ambulance service and the hundreds of millions of dollars spent to cancel two gas-fired power plants in Oakville and Mississauga.
"There is an unbelievable, pent-up anger with the Liberal government," said Progressive Conservative energy critic Vic Fedeli.
"You can feel the anger in the room over the Liberal government and the fact they want them out. I think any of these leadership candidates are going to pay for the sins that they created themselves."
The NDP said people are angry at the Liberals for a host of reasons including cancelling the subsidy to horse racing, closing parks in the north, shutting down the Ontario Northland Transportation Corporation and the cancelled gas plants.
"It's just one thing after another, and it's really a sense of this is a government that has over stayed it's time and sort of lost their vision, and changing the leader won't bring much change," said NDP house leader Gilles Bisson.
"People now see these as a Liberal brand, they don't necessarily see it as the McGuinty government, so a new leader is going to have challenges, no question."
The Conservatives released a video Friday mocking the seven leadership candidates as McGuinty clones.
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