MONTREAL -- To hear "Mr. Three Per Cent" tell it, municipal politics in Quebec operated like a big racetrack -- one where companies bet on different horses in the hope their candidate might gallop to victory and shower them with riches.

In his first day on the witness stand at Quebec's corruption inquiry, Bernard Trepanier began to describe his role in municipal elections where private companies illegally financed campaign bids.

He called them "turn-key" elections. Companies would provide everything, and candidates could step right into their privately financed campaign operation.

In his days as an organizer for municipal parties on the outskirts of Montreal, Trepanier said political parties got cash from companies. Meanwhile, he got cash from parties. And he would be listed as a volunteer organizer, while the payments he received were mostly undeclared and illegal.

In essence, political campaigns were not just democratic contests between candidates -- but a clash between various companies seeking post-election favours.

"There were small battles between area law firms, engineers and contractors, to get city contracts," said Trepanier, as he began his long-awaited testimony.

He earned the unflattering nickname "Mr. Three Per Cent" in Quebec news reports over recent months, as other witnesseses cast him as a central player in corrupt municipal political schemes. Witnesses described a cartel system where companies inflated the cost of public projects, and split percentages with the Mafia, corrupt bureaucrats and Trepanier's once-mighty Union Montreal party.

Such alleged practices would make a mockery of Rene Levesque's landmark reform designed to clean up politics in the 1970s. That law, which has since been copied in numerous jurisdictions and at the federal level, banned corporate donations and limited personal contributions in Quebec.

Trepanier bluntly stated Tuesday that he did not believe Levesque's law had ever been respected -- at least not at the municipal level.

Eventually, when he went on to work for Union Montreal, Trepanier even got paid as a lobbyist from a big engineering company, Dessau Inc., at the same time that he handled fundraising for the party.

The inquiry heard that Trepanier, now 74 and retired, earned more than $900,000 between 2002 and 2010 from Dessau.

Trepanier explained Tuesday that the money from Dessau -- about $100,000 a year -- was for opening doors to contracts at Pierre Elliott Trudeau International Airport.

The airport is federal property, and the inquiry declined to explore those contracts because its mandate is limited to the provincial and municipal levels.

Trepanier described politics as a hobby.

Before he became a local player, he got his start at the federal level with the old Conservative party. He said he first got involved as a volunteer with the now-defunct Progressive Conservative Party of Canada in 1983 in LaSalle, Que.

After the Tories' 1984 election win, he went to Ottawa to work as an aide to several ministers -- starting with Benoit Bouchard, then the minister of transport.

After Bouchard was shuffled to a different portfolio, Trepanier worked with a trio of other Tory ministers -- including Suzanne Blais-Grenier and Andre Bissonnette, who was accused of fraud in a land deal and later acquitted by a jury.

Trepanier's last post was with Monique Vezina in 1987. He would remain involved in the PC party until 1997 and he worked on the victorious leadership bid of Kim Campbell in 1993.

The inquiry will not probe Trepanier's federal activities, as it focuses on its local and provincial mandate.

The former fundraiser from Union Montreal has been identified by witnesses as having collected a three per cent cut from construction contracts on behalf of the party. But another witness this week, ex-party agent Marc Deschamps, said Union Montreal never saw any of that money.

Trepanier has not yet been questioned about what happened to the money; his appearance will resume Wednesday.

Trepanier is one of three major witnesses expected to be heard by the inquiry in the coming days -- the others being former Montreal executive committee chairman Frank Zampino and ex-mayor Gerald Tremblay.

The elderly man appeared nervous as he took the stand Tuesday, coughing frequently.

The judge overseeing the inquiry, France Charbonneau, asked the witness if he needed water. Trepanier responded with a joke: "I don't smoke enough cigarettes."

His hands shook as he tried to pour himself a glass and he warned on two occasions that a previous drinking problem might have caused gaps in his memory.

Before he began working in Montreal, Trepanier said he worked on elections in no fewer than nine municipalities in the greater Montreal area in the 1990s.

He got his local start in 1989 with Gilles Vaillancourt, the long-ruling Laval mayor who quit last fall under a cloud of scandal. Trepanier also worked with Zampino in his first election in St-Leonard, a suburb in east-end Montreal. Zampino now faces fraud charges, along with Trepanier.

Trepanier said he was never paid for his services by either of those two men. He said he had fun working with Zampino, calling his team "a good group, a family."

"A friend is a friend," he said of Zampino.

Trepanier says he took municipal election gigs as a way to build contacts.

In 2002, he started a consulting company he called Bermax. He responded enthusiastically when asked where the company name came from.

"My first name is Bernard, and it's Bernard to the max!" he replied. The company was essentially a lobbying firm, although he never was formally registered as a lobbyist.

Through Bermax, Trepanier had a number of clients including major engineering firms like Desseau and SM, as well as a few communications and advertising firms.

Trepanier told the inquiry he first met Dessau officials while working in Ottawa in 1984, including a company founder and one of his sons. His contract with Dessau in 2002 was signed by Rosaire Sauriol, who this week quit the firm in scandal.