So-called "knockout blows" are uncommon in Canadian politics, however there is a chance for one to land in tonight's English-language leaders' dispute that could shock the surveys and betting chances.

- Tonight's English-language argument is an opportunity for one of Canada's politicians to score points with citizens.
- The odds and surveys are currently predicting a Liberal win, a huge shift from what they were recommending late last year.
- There's likely more betting happening on this Canadian election than any other in history.

The argument scheduled for 7 p.m. ET will provide a chance for Liberal leader Mark Carney to solidify his party's lead, for Conservative leader Pierre Poilievre to turn the tables, and for the leaders of the Bloc Québécois and NDP to try to stand out of citizens.

However, as things presently stand in the polls and on the oddsboard, Canada's 45th federal basic election is appearing like it's the Liberals' to lose.

Here's where the Canadian election odds stand @BET99ON ahead of tonight's English-language dispute for the federal party leaders.

Liberals still leading, Conservatives still tracking, and everyone else still wayyyy back: pic.twitter.com/CAAsQZV1Mm

At Bet99 in Ontario on Thursday morning, the Liberals were still substantial favourites to win the election, at odds of -310. At a suggested probability of 75.61%, those odds are recommending what the surveys have been suggesting: that the Liberals are ahead with citizens at the minute.

The Conservatives, on the other hand, were priced as +220 underdogs and all other celebrations at +7,500. Similar chances exist at other Ontario-regulated sportsbooks, with the Liberals -405 to form federal government at FanDuel on Thursday morning and the Conservatives sitting at +250.

It's been a consistent climb for the Liberals throughout the campaign in both the surveys and Canadian election odds. On April 8, the Liberals were priced as -250 favourites at Bet99, while the Conservatives were +175 underdogs.

There is likely more betting taking place on this Canadian election than any previous trip to the surveys. And there have actually been some huge swings in the odds already.

The resignation of previous prime minister Justin Trudeau earlier this year and President Donald Trump's remarks about Canada becoming the 51st U.S. state have actually been drivers for a resurgence in Liberal popularity. The Grits had been underdogs of +500 or more back in December at some sportsbooks, while the Conservatives were favourites of -900 or much shorter.

Tonight's debate could be another driver for a shift in the chances, as it has been a couple of times in the past. (A French-language argument was hung on Wednesday, and earlier than initially planned so as not to conflict with a key Montreal Canadiens game.)

'You had an option, sir'

Perhaps the most notable example of a huge dispute minute happened more than 40 years earlier. That was when Progressive Conservative leader Brian Mulroney hit then-Liberal Prime Minister John Turner with a stunner during the 1984 federal leaders' argument.

Former prime minister Pierre Trudeau had actually made a raft of consultations on the method out the door, and Mulroney declared to Turner that "You had a choice, sir" to say no to those moves.

After Turner's lacklustre reaction, Mulroney and the Conservatives travelled to a massive win in the election over the currently teetering Liberals.

Will we see something comparable tonight? Probably not, but election bettors may want to keep an eye on the argument all the same.