[7] In 1986, Day was elected to represent Red Deer North in the Legislative Assembly of Alberta as a Progressive Conservative (PC), a position that he held until 2000.

In December 1992, newly elected Alberta premier Ralph Klein brought Day into his cabinet as his minister of labour, a position in which he oversaw controversial changes in his ministry, including layoffs in the civil service.

In this role, Day was credited with working with all of Alberta's Public Service Unions to achieve an unprecedented five per cent voluntary reduction in their collective agreements.

[citation needed] In April 1999, while Day was still Treasurer, he wrote a letter criticizing Red Deer lawyer and public school board trustee Lorne Goddard for representing a defendant who was ultimately convicted on charges of possessing child pornography.

Additionally, Day later wrote a letter to a local paper in his riding as a member of Parliament expressing deep regret "that my former friend Lorne Goddard and his family, have been personally hurt.

After a heavily publicized campaign, Day came in first on the June 24 first ballot of the leadership election with about 44 per cent of the vote, in front of former Reform Party leader Preston Manning and Ontario PC strategist Tom Long.

Instead, he ran in a by-election in the equally safe riding of Okanagan—Coquihalla, British Columbia after incumbent Reform/CA MP Jim Hart stood down in his favour—a standard practice in most parliamentary systems when a newly elected leader doesn't have a seat in Parliament.

[14] A few weeks after Day entered the House of Commons, Jean Chrétien called a snap election for November 27, 2000, which would not give the newly formed Canadian Alliance time to consolidate itself.

But the statement that made headlines in newspapers across the country was Day's acknowledgment that he would indeed consider using the Notwithstanding Clause to block a Supreme Court decision legalizing same-sex marriage, then a distinct possibility that was unnerving many social conservatives.

After being pressed by journalist Matthew Hays on the Notwithstanding Clause question, Day replied "Yes, and the reason I say that is because such a significant number of constituents would reflect concern on that and would want the discussion.

Media covering the Day campaign bus, nicknamed "Prayer Force One", hummed The Flintstones theme song to mock the idea that humans and dinosaurs co-existed.

Day's spokesman Phil Von Finckenstein said the Alliance believes that other theories of creation should be taught alongside evolution in schools, but he also recognizes education is a provincial jurisdiction.

When making a "grand entrance" for a speech at Conestoga College, activist Julian Ichim splashed him with two litres of chocolate milk from the front of the stage, saying he did it to protest Day's "homophobic, anti-immigrant and anti-poor agenda".

A photo-op at a technology firm meant to illustrate a "brain drain" to the US was undermined when the owner reported that he had moved to Canada from the United States eight years earlier.

[26] In mid-campaign, the Alliance candidate in Winnipeg South Centre, Betty Granger, was quoted as voicing concerns about an "Asian invasion" in Canada.

And in the televised leaders' debate, Day held up a handwritten sign saying "NO 2-TIER HEALTHCARE" in large letters to counter a newspaper headline in The Globe and Mail earlier in the campaign.

Progressive Conservative leader Joe Clark retorted, "Mr. Day appears to be running for office as some kind of game show host.

The DRC entered a short-lived coalition agreement with the Tories, which was seen as an attempt by PC leader Joe Clark to reunite the Canadian right on his terms.

In March 2003, Day and Harper co-wrote a letter to The Wall Street Journal in which they condemned the Canadian government's unwillingness to participate in the 2003 invasion of Iraq.

Day later appeared as a speaker at a "Canadians for Bush" rally in the Niagara region, organized by controversial right-wing minister Tristan Emmanuel.

The controversy was heightened when it was leaked to the media that Day had attempted to justify his actions to his party colleagues by circulating an article by David Frum that suggested that Arafat had died of AIDS.

[30] In March 2007, the federal Liberals accused former Alliance MP Jim Hart of having accepted a payment of $50,000 to step aside in favour of Day before the 2000 byelection.

[31] Contacted at his home in the Republic of Georgia, Hart—in a brief email statement to the CBC—did not deny the allegations or impeach the authenticity of the evidence the Liberals had obtained.

[33] In August 2010, Day caused some controversy when he stated the government was "very concerned ... about the increase in the amount of unreported crimes that surveys clearly show are happening".

[47] Day was a member of the board of directors of Telus and a senior strategic advisor to Canadian law firm McMillan LLP from 2011 to June 2020, when he resigned from both positions after comments he made on CBC News Network's Power & Politics amidst the George Floyd protests triggered strong social media reaction including the threat of a boycott of Telus if he did not resign.

In the televised debate, Day's comments included deploring the murder of George Floyd, supporting the right of people to protest and opposing the riots and destruction in US cities.

Day disagreed with Prime Minister Justin Trudeau's claim that Canada is a "systematically racist" country, while noting improvements can always be made.

Day has previously worked as a consultant for Chung, and was appointed to the College's executive as part of the deal - a move students and staff raised alarms about at the time.

Other failed investments include Quest University in British Columbia (which ceased operations in April 2023) and CDI College across Canada, which has been criticized for falsely advertising its accreditation status and job placement rates.