Giambrone continued his attempts to win the south Davenport seat on Toronto city council. When Silva left city council and was elected a
federal Liberal Member of Parliament in
Davenport in the
2004 federal election, Giambrone became a leading candidate to replace him in the
2003 municipal election. With the endorsements of the
Toronto Star,
Now Magazine,
Bloor West Villager newspapers and councillors
Joe Pantalone and
Fred Dominelli, Giambrone defeated
Ana Bailão, Silva's former assistant, by a 51-40 margin in a field of six candidates. As Vice-Chair of the Public Works and Infrastructure Committee, he helped develop solutions to Toronto's garbage challenges, and promoted recycling and organic collection. Giambrone worked with the Mayor to implement a multibillion-dollar road and water infrastructure upgrade program. Toronto Council unanimously approved a September 2007 motion to allow the
Toronto Parking Authority to proceed with a plan to expropriate the Matador, a famed Toronto music hall and cultural landmark. After considerable media attention, an organised group of citizens, including noted author
Michael Ondaatje and folk singer
Sylvia Tyson, lobbied Giambrone to successfully reverse the expropriation. On May 7, 2009, Giambrone sent an email from his mobile phone, warning fellow councillor
Cesar Palacio to "stop messing in my ward" or face "problems". Giambrone apologized for the "hastily composed" email when Palacio distributed copies to local media. Shortly after taking office, he was appointed as a commissioner of the
Toronto Transit Commission (TTC). He also served along with
Greater Toronto Area mayors and regional chairs on the board of
Metrolinx from its inception in 2006 until 2009. During the TTC workers'
wildcat strike on May 29, 2006, Giambrone was prominent in the media representing the TTC's position as commission chair
Howard Moscoe was out of town. After being re-elected in the
2006 municipal election, taking almost 67 per cent of the vote in his ward, Giambrone was elected as Chair of the Toronto Transit Commission on December 6, 2006.
TTC Chairman As chair of the TTC, Giambrone oversaw a large expansion of bus service in Toronto, which saw then-record ridership, and the launch of a new, improved TTC website electronic service advisories, as well as next vehicle arrival information systems, and an affinity discount program for the
Metropass. Some of these ideas were discussed at Transit Camp, a community consultation early in his term as chair. Giambrone also established the station modernization and station renaissance renewal programs for TTC subway stations, the latter in conjunction with the
Toronto Community Foundation. Giambrone also started a program to install bicycle racks on all TTC buses. although naysayers complained that they were not worth the expense and seldom used. Giambrone together with
Mayor David Miller unveiled
Transit City, a $10 billion expansion of light rail into neighborhoods and areas not served by rapid transit, and reaching into the
GTA. Premier
Dalton McGuinty announced funding for Transit City as a component of its
MoveOntario 2020 plan on June 15, 2007. Transit City was also included in Metrolinx's "Big Move" funding plan when it was released on November 27, 2008. On April 24, 2009, Giambrone announced that the TTC had opted to replace its aging fleet of
Canadian Light Rail Vehicles and
Articulated Light Rail Vehicles with 204 new streetcars, procured competitively from
Bombardier Transportation. New streetcars began to enter service in 2012. The deal, valued at more than $1.2 billion, called for the streetcars to be manufactured in
Thunder Bay. Giambrone announced the launch of the TTC's Transit City Bus Plan on August 21, 2009. The plan took the 'network approach' of the Transit City Light Rail Plan and applied it to buses, creating a network of 10-minute service on 21 of its 139 bus routes which began in the fall of 2010. Giambrone appeared on
CP24's monthly television show called
On The Rocket in which he rides a streetcar and discusses daily transit operations, improvements, plans and concerns. In the wake of a sex scandal (see 2010 mayoral campaign), fellow councilor
Brian Ashton called for Giambrone to resign as chairman of the TTC, which had been beset by bad publicity. Ashton said "The TTC is under serious assault around issues of customer relations and performance. The union is now fragmented from the management. I think his moral authority has been totally debased and undermined," said Ashton. "I think mentally he's going to be distracted by both his mayoralty bid and this sex scandal. His ability to come to terms with the TTC issues is tremendously weakened." He did not step down, but also did not seek re-election and so his term as TTC chair ended in December, 2010.
2010 mayoral campaign Giambrone launched a campaign for
Mayor of Toronto in the
2010 municipal election to succeed
David Miller on February 1, 2010, ending it on February 10, 2010. Before Giambrone entered the race, two polls showed him in second place among declared mayoral candidates, though he also had a high unfavorability rating of 40 per cent. He remained a leading candidate until February 9, when the
Toronto Star published an interview with undergraduate student Kristen Lucas, who revealed that she had a past sexual relationship with Giambrone, including acts in his city office. Giambrone apologized for an "inappropriate relationship" and admitted to intimate relationships with women other than his live-in partner, to whom he is now married. In the immediate wake of the revelations, Giambrone initially pledged to continue with his mayoral campaign, Giambrone claimed French lessons as a city council expense, as he was Toronto's representative to the
Francophone Association of Municipalities of Ontario and does interviews with francophone media.
Scarborough—Guildwood provincial by-election On July 5, 2013, Giambrone resigned as co-chair of the candidate search committee and announced his candidacy for the
Ontario New Democratic Party's nomination for the August 1, 2013 provincial by-election in
Scarborough—Guildwood; he won the nomination on July 7 over community activist Amarjeet Chhabra, reportedly by a margin of 18 to 14. Giambrone's nomination was the subject of a threatened legal challenge by Chhabra who alleged that 12 of the 32 individuals who voted at the nomination meeting were not on party membership lists and may not have been entitled to vote according to party rules that require an individual to be a party member for 30 days and to live in the riding in order to be able to cast a ballot. Chhabra said she would not proceed with her attempt to force a new nomination meeting due to the tight time frame before the election. Giambrone came in third place with 28 per cent of the vote, an improvement of 9 per cent from the previous NDP candidate in the 2011 provincial election. ==Transportation career==