Two Toronto-area candidates for the Conservative Party are no longer running for office after questionable behaviour came to light over the long weekend, just as Stephen Harper visited the crucial electoral battleground.

Jerry Bance is no longer the Conservative candidate for the riding of Scarborough-Rouge Park, while Tim Dutaud is no longer seeking election in the riding of Toronto-Danforth.

Bance was dropped after video of a 2012 undercover news investigation by CBC’s “Marketplace” re-surfaced, showing him urinating in a client’s coffee mug, then dumping the contents in a sink before rinsing the mug. He was working as an appliance service technician at the time.

He has since apologized, saying, “I deeply regret my actions on that day. I take great pride in my work and the footage from that day does not reflect who I am as a professional or as a person.”

Dutaud resigned on Monday after he was identified as a man crank-calling women and posing as a disabled person in YouTube videos from 2009.

The controversial videos were leaked on the eve of Harper’s visit to the Greater Toronto Area, a hotly contested region that helped the Conservatives solidify their 2011 win.

The revelations also emerged on Labour Day, a key election milestone that traditionally marks the point when many Canadians head back to work and are likely to begin paying closer attention to election issues.

In his comments Monday, Harper said he expects his party will find new candidates to run in Scarborough-Rouge Park and Toronto-Danforth.

"We expect the highest standards of our candidates and that's why these individuals are no longer candidates," Harper said at an event in Toronto.

Each political party has had their share of controversies this campaign. NDP candidate Morgan Wheeldon was removed from his Nova Scotia riding after a 2014 Facebook surfaced in which he wrote that Israel was trying to "ethnically cleanse the region."

Liberal candidate Ala Buzreba, who was running in Calgary, left the race after offensive tweets she penned as a teenager came to light. In one, she wrote, “Just got my hair cut, I look like a flipping lesbian!!”

The incidents demonstrate just how easily social media can derail a political career, one observer says.

“If there’s anything a little bit controversial, unfortunately nowadays that’s enough to get a candidate fired,” political consultant Michael Geoghegan told CTV News Channel.

It’s a trend that sets a dangerous precedent for future politicians from the Facebook generation.

“Are we basically going to eliminate anyone who has ever said or done anything controversial online? If so, we’re eliminating a huge percentage of Canadians from being eligible for political office,” Geoghegan said.

During his own campaign stop in Toronto earlier on Monday, NDP Leader Tom Mulcair used the Bance urinating incident to mock the Conservatives with a stream of puns. Mulcair said Canadians weren't expecting to see this particular "mug shot" from the Conservatives, and suggested Bance "must be someone who's adept at Stephen Harper's trickle-down theory of economics."

The scandal was trending under the hashtag "#peegate" on Twitter, with many posting jokes and captioned photos about the incident.