Finley, 66, died Saturday after a battle with colorectal cancer that the media-shy campaign general had shared openly with the world in his last months.
He is survived by his wife Diane Finley, a senior federal Conservative cabinet minister, his daughter Siobhan by a previous marriage, and three grandchildren.
“Doug fought a hard and very public battle with cancer. His death is a loss to our family, our friends – and to the entire country," Diane Finley said in a statement.
“Although further details will soon be announced, I do ask that our family have some privacy as we prepare to formally bid farewell to a great man.”
Prime Minister Harper said in a statement that his government has lost a "trusted adviser and strategist" and he has lost a "dear and valued friend."
“A great Canadian has been taken from us, before his time," the statement added.
His legacy, Doug Finley told CBC's The Current in late December 2012, "will be my family."
But the gruff, Scots-raised campaigner allowed that, "If people think of me as part of a movement, part of an organization that perhaps shifted a little the political landscape in Canada, I think that's a fairly significant thing."
It was typically self-effacing Finley understatement.
He was a critical cog at the top of the finely tuned political machine that propelled Stephen Harper into the party leadership and on to 24 Sussex Drive.
The former director of operations for the Canadian Alliance party, Finley helped shepherd Harper's Conservative party leadership bid and then the 2004, 2006 and 2008 federal Conservative election campaigns.
"We could never have won (power) in 2006 without Doug Finley's organizational ability," Tom Flanagan, Harper's former campaign strategist, wrote in his 2007 book "Harper's Team."
"The transition from Tom to Doug as the campaign (management) guy was an essential turning point in many different ways," says Ian Brodie, Harper's former chief of staff and a close Finley friend.
"He took a load off of Stephen in terms of being ultimately the arbiter of disputes about how we were going to do things ... to run the machinery of the campaign."
Jim Armour, an early communications director with the Alliance and Conservatives, said Finley was often mischaracterized as the "architect" of their rise to power. Instead, Armour said Finley was the builder who paid attention to detail and ensured it was done properly.
"He actually built the majority mansion following on Harper's plans."
Finley was born in Exeter, England, on July 25, 1946 but was raised in Scotland and maintained his distinctive highland growl to the grave.
A huge soccer fan of Manchester United and Glasgow Celtic, Finley was steadfast in his defence of the Scots James Bond, Sean Connery, although his political allegiances changed significantly over the years.
He was an early supporter of the leftist Scottish National Party, worked for the Liberals in Quebec in the 1970s and the Ontario Progressive Conservatives before finally finding his true political home with the Canadian Alliance and Conservatives.
A heavy smoker who enjoyed a dram of whiskey, Finley did all this while building an executive career in the aerospace industry.
Described by friends as a classic Scot with a gruff exterior and warm heart, it was Finley's hot temper that defined what little public persona he had.
As the man in charge of Conservative candidate nominations and political training, Finley was the firefighter and enforcer when candidates went off script. The shell-shocked accounts of dumped candidates were one of the few public windows into Finley's working world, providing some hair-raising reading.
"It's better than being called Casanova or something," Finley growled to the CBC when asked in 2012 about his pitbull label.
Senior executives, whether in business or political campaigns, must "wear many masks, many different personae," he told the public broadcaster.
"Every now and again one has to adopt a sort of iron fist without the velvet glove."
Garth Turner, a short-lived, maverick MP under the Harper Conservatives, once described Finley this way: "He lives not just to kill the competition but, once he's killed them, he wants to stab and drown them. He is a master strategist and I have great respect for his political skills. He's ruthless."
On the other side of the ledger was the imperturbable Finley.
"I always found him extraordinarily patient with trying to bring people up to speed on the ropes, to show people the ropes," says Brodie.
Finley could be found at the centre of various Conservative party contretemps, including the alleged million-dollar life insurance offer to dying Independent MP Chuck Cadman for his vote during the 2005 minority Liberal minority budget vote.
It was Finley who engineered one of the party's single most successful fund-raising gambits by lodging a public complaint over "collusion" by CBC reporter Krista Erickson with a Liberal MP during 2007 hearings into Brian Mulroney's suspect business dealings.
Erickson's actions were portrayed in a Conservative fund-raising letter as evidence of bias by the public broadcaster.
The letter raked in donations and — no doubt — tickled Finley's funny bone. Left unsaid was that the same CBC reporter had stayed with her Conservative MP boyfriend in the party's hotel in Charlottetown for their summer caucus in August 2007 — a hotel barred to all other media.
Finley was also deeply implicated in a 2006 campaign financing scheme, known as the in-and-out affair, for which the Conservative party eventually pleaded guilty and paid the maximum fine. In return, charges against Finley and Irving Gerstein, the party's chief fundraiser, along with two other individuals were dropped.
When Harper appointed him to the Senate in 2009, the late NDP leader Jack Layton called the appointment "just odious."
But Finley had other personas.
Fiercely loyal to his friends and engendering true fealty in return, Finley helped organize the Scottish Society of Ottawa in his spare time.
When his end-of-life media interviews in late 2012 attracted the usual bileous political Internet hate commenters, Finley's granddaughter took to the comment boards in fierce defence.
"My grandfather is a great man. Through his journey he kept his head held high, and can still make jokes about it .... I am Emma, 13 years old and I love my papa more than you will ever know," she wrote.
Friends also remark on Finley's enduring love for his wife of 30 years, Diane, whom he met when she was a summer hire at Rolls Royce where he was an executive.
On Valentine's Day 2013, Doug and Diane Finley appeared together on Don Martin's CTV politics show PowerPlay.
In telling fashion, Doug fondly and humorously described the many kilts at their wedding: "Probably one of the few times in Ontario history, at least in those days, where the preacher, the bride and the groom all wore skirts.
"Quite common now, but at least we had two sexes involved, you know."
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