OTTAWA -- In this election, Hamilton, Ont., has turned into the city of love.

The metro area of about 600,000 on the western tip of Lake Ontario has seen the leaders' buses carrying the NDP, Liberal and Conservative tours glide through at least six times in the first five weeks of the campaign.

With only four ridings, Hamilton doesn't have the electoral bounty of Toronto, Vancouver or Montreal. But depending on who you talk to, all four Hamilton ridings could be in play, and in close races, the leader's appearance can generate a needed bump.

"A visit will generate growth and support for Mr. Trudeau," said David Rodier, senior vice-president of corporate communications at public relations firm Edelman and a campaign tour veteran, who did tour bus logistics as the "wagon master" for the Liberals in 2015 and 2019.

"Generally speaking, I've always been told that it's two to three per cent."

Jamie Ellerton, principal at Toronto's strategic and public relations firm Conaptus and the media relations manager on Andrew Scheer's Conservative bus in 2019, said a leader's visit does generate more local media coverage.

He said there are diminishing returns when leaders spend too much time in Toronto and Vancouver because the markets are so big and all the leaders are in those cities a lot.

"But take out those two big cities, the impact of the tour in terms of driving a message, and igniting a conversation with Canadians, does have a very big impact in terms of what people are talking about," he said.

The suburbs of Toronto, Vancouver and Montreal are, as expected, the biggest draws.

They're also where most of the closest races are expected.

As of Sept. 16, Trudeau had visited at least 70 ridings, of which 15 were in the 905 region surrounding Toronto, eight were in the Vancouver suburbs of Surrey, Richmond, Delta and Coquitlam, and eight were on the north or south shore of Montreal.

NDP Leader Jagmeet Singh has made 56 tour stops, six each in the 905 and suburban Vancouver, while Conservative Leader Erin O'Toole has visited about three dozen ridings, including six in the 905, and five in the Vancouver suburbs.

O'Toole's campaign stops are so much lower because he chose to make 10 announcements and hold virtual town halls from a ballroom at the Westin Hotel, just a few hundred metres from Parliament Hill.

Ellerton said the virtual events reach more people but don't generate the same kind of media coverage or energy as an in-person stop.

"When you're talking to those voters and those engaged with the town hall, definitely you're connecting and you're getting that engagement for those people but for a broader audience, and broadcasting that out to a large swath of a larger audience, it doesn't quite translate the same way," he said.

Ellerton said where a leader goes is not random, and typically the stops are mapped out with a lot of thought before the campaign starts. The plan can change as campaigns change how a party is faring.

"When the Liberals are doing really well, they don't spend too much time in Montreal," he said. "For the Conservatives, they don't spend too much time in Calgary or Edmonton. So when you start to see leaders spending a lot of time in places where they typically don't, it means they are, from a campaign strategy standpoint, looking to shore up their numbers and keep those places in the fold."

Rodier said the tour tries to get to every province once as quickly as possible at the start and to as many ridings as possible in the final week or so.

This year, Trudeau made it to six provinces in the first six days, and to all 10 by day nine. He is still the only leader to have travelled to a territory, visiting Iqaluit on Aug. 30.

O'Toole made it to all 10 provinces by day 14.

Singh hasn't made it to New Brunswick or Prince Edward Island since the official campaign began, but toured both the week before Trudeau called the election.

Rodier also said that parties have a lot of data on individual ridings, and they'll be very aware which ones are close and can benefit from a quick leaders' photo op. Trudeau tends to use stops in urban areas to showcase all the candidates from the region, not just one.

Overall the leaders haven't varied much from what their expected tour stops would be. Trudeau is mostly in suburban Toronto, Vancouver and Montreal. O'Toole is spending the most time in the 905 and in and around Quebec City.

Singh appears most focused on the Windsor area -- where the NDP lost two seats in 2019 -- as well as going after Liberal heartland seats in Toronto. He's also spending a lot of time in the Vancouver suburb of Burnaby, where his own seat is.

He is the only leader to make more than one visit to his own riding, Burnaby South. Trudeau visited his Montreal riding of Papineau the afternoon he called the election, while O'Toole has not gone to his Durham riding at all.

Green Party Leader Annamie Paul holds the clear record for campaigning in her own riding -- she has barely campaigned anywhere else, as she tries to win a seat for the first time, and admits many candidates don't want her to visit as the party's internal squabbles continue.

This report by The Canadian Press was first published Sept. 17, 2021.