A spring election in Ontario now seems inevitable after yet another big night for Ontario NDP Leader Andrea Horwath.
The byelection win in Niagara Falls on Thursday marked the fourth seat the opposition party has gained since the last provincial vote in 2011.
It has been almost 100 years since any party in Ontario has picked up that many seats between general elections.
The NDP's Wayne Gates won in Niagara Falls with 39.4 per cent of the vote, beating out PC candidate Bart Maves, who took 36.8 per cent. The Liberals' Joyce Morocco, who had hoped to replace outgoing Liberal MPP Kim Craitor, captured just 19.4 per cent of the vote.
In 2011, Liberals had 35.9 per cent support in the riding against 34.8 per cent for the Tories and 26.3 per cent for the NDP. The Liberals thus lost almost 17 points of their vote share, the bulk of it going to the New Democrats who, despite the drop in turnout, increased their raw vote haul by more than 2,000 ballots.
But Tim Hudak's Progressive Conservatives also performed well.
In Thornhill, the PCs' Gila Martow retained the riding for the party with 48 per cent of the vote, compared to 41.5 per cent for the Liberals' Sandra Yeung Rocco. Both parties increased their vote share from the previous election, with the Tories up 1.3 points and the Liberals gaining 0.6 points. The NDP dropped from nine per cent in 2011 to 6.8 per cent last night.
With the NDP winning yet another riding — they took Kitchener-Waterloo from the PCs in 2012 and London West and Windsor-Tecumseh from the Liberals in 2013 — Horwath should feel confident enough in her party's ability to win when it counts to pull the plug on Kathleen Wynne's minority government.
For the Progressive Conservatives, the night was not as good as it could have been. They had some hopes of winning Niagara Falls, a riding adjacent to Hudak's, but held on to Thornhill and took, by far, the most votes in both ridings.
Of the ballots cast in Thornhill and Niagara Falls, 41.6 per cent when to a Tory candidate. The Liberals took 28.9 per cent of the vote in both ridings, while the NDP took 25.4 per cent. For a party that has been clamouring for an election since before Wynne became premier, these results are unlikely to dampen its enthusiasm.
Compared to the average vote share across the two ridings in 2011 (which discounts the effect of turnout), the PCs picked up 1.6 points and the New Democrats 5.4 points. The Liberals dropped 7.9 points, thanks primarily to their poor showing in Niagara Falls.
It was a bad night for the Liberals, as byelections have generally been for this government. But the results in Thornhill, like past votes in Vaughan, Scarborough-Guildwood, and Etobicoke-Lakeshore, suggest the party is still competitive in the area around Toronto.
However, the collapse of the Liberal vote outside of the GTA that was seen in Niagara Falls was also replicated in the byelections in Kitchener-Waterloo, Windsor-Tecumseh, and London West. If that pattern continues in a general election, Liberals could be reduced to their enclaves in Toronto and Ottawa, leaving Horwath and Hudak to battle it out in the rest of the province.
Who would prevail in such a fight is difficult to determine, though Hudak has the inside track.
With decent prospects of both parties to increase their representation in Queen's Park and take advantage of Liberal weakness, there is little to stop the government from collapsing and an election to be held within months.
Éric Grenier taps The Pulse of federal and regional politics for Huffington Post Canada readers every week. Grenier is the author of ThreeHundredEight.com, covering Canadian politics, polls and electoral projections. You can pre-order his eBook, "Tapping into the Pulse", a retrospective of polling in 2013, here.
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