TORONTO -- Only the New Democrats can prevent the Progressive Conservatives under Doug Ford from forming government in Ontario next week, NDP Leader Andrea Horwath said Friday in her most direct pitch yet to Liberal voters.

Speaking at a campaign stop in Toronto, Horwath said she expected a close election on Thursday.

"One thing is certain: Ontarians will elect a new premier to replace Kathleen Wynne," Horwath said in the Liberal premier's own riding. "The choice is between me and Doug Ford, (and) to those who have voted Liberal in the past, I invite you to join us to stop Doug Ford and vote for the kind of change that Ontario needs."

In past elections, voters opposed to the Conservatives have tended to coalesce around the Liberals as their best bet.

This time, however, it appears the strategic vote is poised to break in Horwath's favour. Horwath's voting pitch -- typically seen as Ontario and federal elections move into their final stretches -- comes as polls suggest either she or Ford will become Ontario's next premier.

Myer Siemiatycki, a politics professor at Ryerson University, said polling suggests a shift to the NDP away from the Liberals began unusually early this campaign given the "fear factor" around the Tories, who've been criticized for not detailing how they'd pay for their campaign promises.

"In the past, the Liberals have typically -- either federally or provincially -- been regarded as, and have been, the stronger party, so the messaging has been to NDP supporters not to waste their vote," Siemiatycki said.

Wynne, who has been making her own last-ditch appeal to both Liberal and NDP voters to go with her as the voice of pragmatic experience, has also tried to frame the election as between her and Ford's Progressive Conservatives -- despite polls suggesting the Liberals are trailing badly.

In an interview with The Canadian Press this week, Wynne said it was too early to discuss strategic voting -- or whether it was going to break in favour of the New Democrats for the first time in years.

"I don't think we're there yet. I don't think we can actually say that," Wynne said. "The falling off of Ford's support is just becoming clear. We won't know for a few more days exactly where people are going to go. That's my sense."

On Friday, Wynne stuck to her defensive pitch -- that she would still make the best leader -- saying people need to be "very careful" in deciding who would be best at building the province.

Horwath, who also planned a campaign stop Friday in St. Catharines -- another seemingly impregnable Liberal fortress -- said she can sense the changed sentiment as she railed against both Wynne and Ford.

"Ontario wants change," Horwath said Friday. "Doug Ford is not the kind of change Ontario needs."

Brenna Keatinge, a self-described "very progressive" Toronto resident in the normally Liberal riding of St Paul's, said she used to consider voting Liberal when the party seemed the only viable contender against the Conservatives. This time, she said she planned to cast her ballot on June 7 for the NDP to try to keep Ford out of the premier's office.

"If I think there is a really strong chance the Conservatives would get in, then I would tend to be more strategic and vote Liberal," Keatinge said. "But this time around, the NDP actually has a chance so … I think overall voting NDP makes the most sense."

Peter Graefe, a political science associate professor at McMaster University, said the anti-Tory coalescing appears to have started in the Ontario campaign much earlier than usual.

"The Liberal and NDP campaigns are set up on this idea that there's going to be the first part of the election -- which is a primary between the two of them and the winner will then go and fight the Conservatives," Graefe said.

"What's really remarkable this time is that within about two days of this campaign starting, that decision had more or less been made -- that it was quite clear that it was going to be the NDP against the Conservatives."

Brenda Stockdale, 54, a Cambridge, Ont., resident, might be one of those anti-Ford voters the Liberals have traditionally won over, but not this time. Her faith in the Liberals was shaken and her vote will go to the NDP, she said.

"They're for the working people. I'm the working people. And that's important to me," Stockdale said after attending a Horwath rally in Kitchener, Ont., this week.

"Our health care system and our education system has been cut so much," said Stockdale, a health educator. "(Horwath) gives me hope that she's going to change that."

Ford's claim to be "for the people" is just a "facade," she said.

-- with files from Peter Goffin and Shawn Jeffords.