As Mayor Rob Ford returned to Toronto City Hall and addressed the addiction issues that led him into rehab, some of the people vying for his job this fall said residents should be choosing a new mayor this fall.

Ahead of Monday, Ford had been away from his office for two months getting addiction treatment at GreeneStone, a facility north of the city in cottage country. He used his return to pledge that he is clean and will continue treatment.

He also recommitted to winning the election, saying he hopes to lead the city as mayor for many years to come.

Olivia Chow, who is also seeking the mayor's job in the Oct. 27 municipal election, said Ford's sobriety is not the issue. She called him a "failed mayor."

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Mayoral candidate Olivia Chow, seen above in a photo taken last month, said Monday that Ford is a 'failed mayor.' (Nathan Denette/Canadian Press)

"I wish him well. Substance abuse is a disease, and he is sick," she said. "But Rob Ford needs to be replaced."

She said his apology seemed sincere, but reiterated he has failed the city with his policies.

Chow said she would not call on him to step down, however. She wants voters to decide that on election day.

"The people of Toronto need to issue a verdict," she said. "Let us collectively, democratically send Mr. Ford out of office."

Rival candidate John Tory said there are too many unanswered questions for Ford to be able to continue as mayor.

He said Ford had "massively embarrassed" the city and is "incapable of working with council and other levels of government."

Tory agreed it was an emotional day for Ford, but pointed to other problems with his mayoralty besides addiction.

For instance, he said, Ford was "mixing private and public business" as mayor, referencing an allegation of inside lobbying at city hall.

Tory said the risk is too high to have Ford continue as mayor.

'Years of dereliction of duty'

When Ford made his remarks on Monday, he made a specific reference to Karen Stintz, a fellow councillor and mayoral contender about whom he made lewd remarks.

"To my fellow councillors and especially to Karen Stintz, for my hurtful and degrading remarks, I offer a deep-felt apology for my behaviour," Ford said.

Stintz issued a statement saying that the mayor could reach out to her, if he desired to do so.

"If the mayor wants to apologize to me, he's got my number and he can call. It's a private matter for him to discuss with me directly," she said.

But Stintz added that Ford has more to apologize for.

"I'd rather he apologize to the City of Toronto for years of dereliction of duty, abject failure to trim the budget, zero leadership on transit, and years of offensive antics, bigotry, and racism," she said.

Stintz said that if she is elected as mayor, she will "bring dignity back" to the mayor's office and get the city back to business.

While Ford was away, Chow released several attack ads characterizing the mayor's behaviour as embarrassing. Tory framed his attack at Ford in the form of a 10-point personal "code of conduct" he vows to adopt if elected.

Chow, Stintz and Tory are in a crowded field of candidates seeking the mayor's job this fall.