COLDWATER, Ont. -- Progressive Conservative Leader Patrick Brown will have a seat in the Ontario legislature when it resumes in a little over a week after winning a byelection Thursday.

Brown, formerly a Conservative MP in nearby Barrie, won the party leadership in May.

He resigned his federal seat but spent the last few weeks of the legislative session as a leader sidelined without a seat in the house.

Brown predicted that his increase of the vote share in the riding of Simcoe North could foreshadow a broader electoral victory in the 2018 provincial election.

"If you added 10 per cent to the conservative vote in every riding around the province, well in two years and nine months I think we'd be looking at a Progressive Conservative majority government," he said to a victory party packed with caucus members and supporters.

Longtime Progressive Conservative MPP Garfield Dunlop resigned his Simcoe North seat this summer so Brown could run.

During the leadership race Dunlop was one of Brown's most outspoken critics, but struck a much more conciliatory tone when resigning his seat for the leader, and endorsed him in Simcoe North, which is also held by the Conservatives federally.

Brown spent the summer putting to work the canvassing and campaign organization skills that saw him beat out caucus favourite Christine Elliott for the party leadership.

Early results showed Brown garnered more than 50 per cent of the vote, beating Liberal candidate Fred Larsen, who lost to Dunlop in the previous two elections, and NDP candidate Elizabeth Van Houtte --

a professor of social work at Lakehead University.

In addition to rival candidates, Brown had also been battling the federal election for voters' attention.

Brown said in an interview last week that voters had no trouble distinguishing between the two campaigns, making it clear they are fed up with the provincial Liberal government, especially its decision to sell Hydro One.

The Liberals did not let Brown take the riding without a fight.

Deputy premier Deb Matthews sent a letter to 47,000 homes in Simcoe North portraying Brown as an extreme right winger who voted in Parliament "to take away the right of same-sex couples to marry and...to examine changes to the Criminal Code to eliminate a woman's right to choose."

Matthews also pointed out that Dunlop had criticized Brown for opposing an update to Ontario's sex-education curriculum, and said his resignation "shows there's no room left for moderates in Patrick Brown's extreme-right PC party."

Dunlop slammed Matthews' letter as he introduced Brown at his victory party.

"Deb Matthews should hide her head in shame for that stupid letter she sent," he said. "That backfired."