So-called "knockout blows" are uncommon in Canadian politics, however there is a chance for one to land in tonight's English-language leaders' argument that might shake up the polls and betting odds.

- Tonight's English-language debate is an opportunity for one of Canada's politicians to score points with citizens.

• The odds and polls are currently predicting a Liberal win, a big shift from what they were recommending late in 2015.
• There's likely more betting occurring on this Canadian election than any other in history.
  
  The dispute arranged for 7 p.m. ET will present an opportunity for Liberal leader Mark Carney to strengthen 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 currently 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 chances stand @BET99ON ahead of tonight's English-language argument 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 an indicated likelihood of 75.61%, those chances are recommending what the surveys have actually been recommending: that the Liberals are ahead with voters at the moment.
  
  The Conservatives, on the other hand, were priced as +220 underdogs and all other parties at +7,500. Similar odds exist at other Ontario-regulated sportsbooks, with the Liberals -405 to form government at FanDuel on Thursday morning and the Conservatives sitting at +250.
  
  It's been a steady climb for the Liberals throughout the project in both the polls and 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 been some big swings in the chances already.
  
  The resignation of previous prime minister Justin Trudeau previously this year and President Donald Trump's remarks about Canada ending up being the 51st U.S. state have been catalysts for a revival 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 shorter.
  
  Tonight's argument could be another driver for a shift in the odds, as it has actually been a few times in the past. (A French-language argument was hung on Wednesday, and earlier than initially meant so as not to dispute with a key Montreal Canadiens game.)
  
  'You had an option, sir'
  
  Perhaps the most significant example of a huge argument minute occurred more than 40 years earlier. That was when Progressive Conservative leader Brian Mulroney struck then-Liberal Prime Minister John Turner with a stunner during the 1984 federal leaders' dispute.
  
  Former prime minister Pierre Trudeau had actually made a raft of consultations en route out the door, and Mulroney declared to Turner that "You had an option, sir" to state no to those relocations.
  
  After Turner's lacklustre action, Mulroney and the Conservatives cruised to an enormous win in the election over the already teetering Liberals.
  
  Will we see something similar tonight? Probably not, however election wagerers may wish to watch on the debate all the same.