Michael Chong's Reform Act passed in the upper house late Monday by a vote of 38-14, with four abstentions.
Chong sat in the gallery to watch the nerve-wracking finale to his 19-month crusade to empower MPs and dilute the power of party leaders.
"It was surreal, I couldn't believe that it was actually taking place," he said in an interview moments after the final vote.
"We weren't sure when the vote was going to take place ... or if at all. There was a real risk that the bill was going to be filibustered out and that didn't happen."
Chong was "thrilled" with the outcome and predicted it will mean MPs will be able to do a better job representing their constituents.
"It will lead to freer votes in the House of Commons, where members of Parliament can, on occasion, break ranks with their party to represent their constituents views and that is a significant change from the status quo."
Among other things, the act is designed to give MPs in a party caucus the power to trigger a leadership review, and to subsequently vote to oust their leader.
Two Conservative senators, David Wells backed by Denise Batters, introduced an amendment last week that would have neutered that specific part of the private member's bill.
Passing the amendment would have effectively killed the bill, since it would have forced it back to the House of Commons, which adjourned last week in advance of an anticipated October election.
Wells' amendment was rejected Monday by a vote of 46-14.
But about a dozen Conservative senators who strenuously opposed the bill continued to try several more procedural manoeuvres to block it.
Sen. Yonah Martin moved to adjourn final debate on the bill until Tuesday. That motion was defeated by a vote of 47-7.
Then Batters moved another amendment. After brief, acrimonious debate, that amendment was also defeated by a vote of 39-12.
Finally, opponents allowed the bill to be put to a vote.
In addition to giving MPs control over their leader's fate, Chong's bill will give them the power to expel and reinstate colleagues from their caucus, currently the preserve of party leaders. It will also give them the power to select their caucus chairperson.
In a bid to win all-party support in the House of Commons, Chong watered down some elements of his original bill.
He agreed, for instance, to drop a proposal to strip leaders of their power to determine who can run as a candidate for their parties. Instead, the bill now requires each party to designate a person or entity to approve nominations, leaving the possibility that the leader will continue to call the shots.
He also agreed to subject all elements of the bill to a vote by each party's caucus after each election. They could choose to adopt the rules, modify them, or go with the status quo.
Chong said the bill would not have passed either the Commons or the Senate without the changes, some of which he insisted actually strengthened the legislation.
"It demonstrates that multi-party support can be built to reform Parliament," he said.
But while Chong was celebrating, a fellow Conservative backbencher, Russ Hiebert, was expressing outrage that his own private member's bill appears doomed in the Senate.
Hiebert sent an email to his caucus colleagues, obtained by The Canadian Press, in which he said he's learned that Conservative senators have decided to adjourn the Senate on Tuesday without voting on his bill.
"This is outrageous!," Hiebert wrote. "To walk away now is inexcusable."
Hiebert's bill would require labour unions to publicly disclose how they spend their money. The bill, which has been widely denounced as unconstitutional, has been stalled for days during third reading debate as Liberal senators attempt to run out the clock.
Also on HuffPost