A Toronto businesswoman who accused Rob Ford of grabbing her buttocks and behaving oddly at a gala event a year ago has joined the race to unseat the city’s embattled mayor.

Sarah Thomson became the 40th mayoral candidate to enter the campaign when she filed her nomination papers at city hall Thursday morning.

Thomson, the publisher of Women’s Post magazine, arrived on a horse-drawn wagon to demonstrate how far Toronto has come in regards to public transit and to draw attention to the core of platform – the desperate need to invest in and improve the existing transit system.

Outside city hall, Thomson told reporters she wants tolls on the Don Valley Parkway and Gardiner Expressway for “non-residents.”

She said the city’s next subway expansion should be a “Yonge Street relief line.”

Thomson said she supports “underground” light-rail transit as an extension to the Bloor-Danforth subway line in Scarborough, but the relief line should be built first.

Thomson joins a crowded race that already includes Ford and challengers Olivia Chow, David Soknacki, Karen Stintz and John Tory.

Thomson said she expects to have a seat at upcoming debates, which are normally reserved for the front-runners.

“I think I’m the only candidate that’s really going to talk about the hard issues,” Thomson said. “We have to invest. We have to look at building our city.”

This is the second time Thomson has run for mayor of Toronto.

In 2010, Thomson dropped out of the race about a month before the election because her campaign “ran out of money,” she said Thursday. After withdrawing her candidacy, Thomson threw her support behind George Smitherman, who was the runner-up to Ford.

Thomson told reporters her name will be on the ballot when voters head to the polls in October.

“Am I going to stick around? Oh, yeah. I’m in this to win this," she said Thursday.

A year after she pulled out of the mayoral race, Thomson ran for MPP in central Toronto.

She was the Liberal candidate in Trinity-Spadina, where she finished second to long-time NDP MPP Rosario Marchese in the 2011 provincial election.

In March of 2013, Thomson accused Ford of making suggestive comments and grabbing her buttocks as they posed for a photo at a dinner held by the Canadian Jewish Political Affairs Committee. She claimed the mayor was acting strangely and something was "wrong" with him.

Ford denied the allegations.

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