Many analysts believe Progressive Conservative Leader Tim Hudak, who began the campaign as the clear front-runner, will fall short in his efforts to loosen Premier Dalton McGuinty's grip on office.
"Tim Hudak blew it," said Larry Savage of Brock University's political science department.
In all, about 8.5 million people are eligible to cast ballots at a time when chilly economic winds have been buffeting the province.
McGuinty, who is hoping to defy pre-campaign predictions by winning a third straight term — something no Liberal has done in Ontario for more than a century — has been pressing his competence and experience as a fiscal manager.
It's a message that appears to have resonated with voters despite their anger at a string of his broken promises that should have washed Hudak into the premier's chair.
"We all kind of concluded it was a done deal," said Bryan Evans, a political science professor at Ryerson University.
"The Conservative campaign simply read it wrong and made too many strategic blunders along the way."
Analysts point to Hudak's constant banging of the anti-McGuinty drum rather than offering people a clear reason to vote for him instead.
He also insisted on pressing wedge issues that sparked a backlash and distracted from any positive message he tried to get out, observers say.
"He has not succeeded in getting people to trust him," said Laure Paquette, who teaches political science at Lakehead University in Thunder Bay, Ont.
"People don't trust the Tories to be tolerant."
According to the latest polls, Andrea Horwath will likely lead her New Democrats to levels of popularity unseen since her party's much maligned five years in office under Bob Rae in the early 1990s.
Analysts credit Horwath's feisty style along with an updraft from the her late federal counterpart Jack Layton for making a positive impact on voters.
However, they don't expect the NDP to make a dramatic breakthrough as Rae did in 1990 but could, polls suggest, hold the balance of power if McGuinty fails to win a clear majority of at least 54 seats.
"The way the vote splits will determine everything," Savage said.
Generally, low turnouts tend to favour the incumbents.
That means getting the vote out will be especially crucial for the Tories and NDP, which could prove a challenge if recent trends hold.
Turnout in the 2007 election plunged to historic lows, with barely more than half of eligible voters bothering to cast a ballot.
At dissolution, the Liberals held 70 seats, the Tories 25, and the New Democrats 10. Two seats were vacant.
The Liberals picked up 42.3 per cent of the popular vote in 2007, the Tories 31.6 per cent and the New Democrats 16.8 per cent. The Greens, who didn't win a seat, had the support of eight per cent of voters who cast ballots.
In all, 21 parties are registered for Thursday's vote.By Colin Perkel, The Canadian Press EDITORIAL ENDORSEMENTS
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