Conservative and Liberal senators think they have the numbers to stop Bill C-290. And if enough of them stand their ground, it would mark the first time the Upper Chamber has rejected legislation unanimously passed by members of Parliament.
"I've talked to people individually who indicate that they're going to vote against it," Conservative Sen. Norman Doyle said in an interview.
"I'm thinking that we probably have enough people in the Senate to kill it."
The proposed legislation would repeal the Criminal Code section that prohibits betting on a single race, fight, sporting event or athletic contest.
If passed into law, each province would get to decide whether to allow single-game betting. Currently, the provinces only allow "parlay betting," or wagering on multiple outcomes on a single ticket — such ProLine in Ontario.
MPs passed Bill C-290 and the legislation just needs to pass a third and final reading in the Senate to become law.
But interviews with Conservative and Liberal senators suggest the majority of them will vote against Bill C-290.
"There's a significant number of us (opposed to the legislation)," said Conservative Sen. Linda Frum.
"It's not a handful. The opposition to this is more significant."
Liberal Sen. George Baker said he expects the "vast majority" of his caucus and about half of the Conservatives to vote against the bill.
"I think the bill will be defeated," he said.
The senators who spoke to The Canadian Press all expressed concern about the lack of debate in the Commons.
"It kind of flew through the House without a great deal of scrutiny," Frum said.
"It had one day at committee, and they really didn't study the bill. They didn't invite the stakeholders who will be impacted by the bill. So I'm not sure it really had the proper level of study or scrutiny."
Next week is a break week for the Senate. But senators expect to debate the bill when they return the following week. It's likely the earliest the bill could come to a vote is Nov. 22, although some expect an early December vote.
Professional sports leagues strongly oppose the bill. They argue allowing single-game betting could open a Pandora's Box of match-fixing and social problems associated with gambling.
National Hockey League deputy commissioner Bill Daly was scheduled to appear before a Senate committee Thursday, but the ongoing labour talks and poor weather in New York kept him far away from Parliament Hill.
In a written submission, the NHL urged the Senate not to pass the bill, saying the game's integrity is essential to its popularity.
"We firmly believe that legalized sports betting threatens to compromise that integrity, and that the single-game betting scheme that Bill C-290 seeks to decriminalize poses a particularized and unique threat in that regard," the league wrote.
"Such wagering poses perhaps the greatest threat to the integrity of our games, since it is far easier to engage in 'match fixing' in order to win single-game bets than it is in cases of parlay betting (as currently exists in Canada), where bets are determined on the basis of multiple game outcomes."
The league warned the bill would have game-changing ramifications.
"If single-game sports betting becomes a publicly fostered and sponsored institution, then the very nature of sports in North America (including in the National Hockey League) will change, and we fear it will be changed for the worse."
Other professional sports leagues also oppose the bill. A top Major League Baseball official and the head of the Toronto Blue Jays have both appeared before the Senate committee to voice their opposition to the passage of Bill C-290.
"When gambling is permitted on team sports, winning the bet may become more important than winning the game; the point spread or the number of runs scored may overshadow the game's outcome and the intricacies of play," Blue Jays president and CEO Paul Beeston said last month.
"If large numbers of our fans come to regard baseball only or even partially as a gambling vehicle, the very nature of the sport will be altered and harmed. We want fans to root for the home team to win. Likewise, we want our athletes to know that they are being cheered to win."
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