“Perception is everything (in politics)” or “Perception is reality (in politics)” means that what the public perceives to be true is important, not if something is actually true. If a politician is perceived to be honest or dishonest, or if crime is perceived to be going up or down, that is “everything” (or “reality”).
 
The saying has been popular in both the United States and in Canada since at least the 1970s.
 
     
Google Books
Industrialized housing. Hearings, Ninety-first Congress, first session. July 9, 23 and 24, 1969
By United States. Congress. Joint Economic Committee. Subcommittee on Urban Affairs.
Washington, DC: U.S. Government Printing Office
1969
Pg. 177:
In this town, perception is everything, and baseline reforms make it easier to balance the budget, in my judgment.
 
Google News Archive
12 January 1978, Montreal (Quebec) Gazette, pg. 8, col. 1:
Because I believe that in politics perception is reality, my principal objection is that the move of an important company such as Sun Life is symbolic and has consequences far beyond the loss of thousands of jobs and millions of dollars to Quebec.
(Letter by Richard B. Holden—ed.)
 
20 March 1979, New York (NY) Times, “In the Subways, Koch Says, Perception of Crime Is Real” by Lee Dembart, pg. B10:
New York City’s assualt on subway violence is as much a response to the perception of crime as to the fact of crime, Mayor Koch says. Whether or not the perception is accurate, the Mayor asserts, it is widely held, it appears to be influencing people’s behavior and it must be dealt with.
 
“In this particular case, perception is reality,” Mr. Koch said in an interview in his office yesterday. “If a person believes that he is in special danger, he is going to avoid the subways. I am responding not to the headlines, but to the anxieties raised by the facts.”
   
21 March 1982, Seguin (TX) Gazette-Enterprise, “Cconservatives who seem not to care” by James J. Kilpatrick, pg. 13A, col. 1:
In politics, perception is everything.
   
Time magazine
Essay: Marshal Potemkin, Meet Your Fans
By HP-Time.com;Otto Friedrich Monday, Nov. 28, 1983
Marshal Grigory Potemkin, one of the more artful lovers of Catherine the Great, accomplished many things during his long domination of Russia, but he is best remembered for an illusion. To impress Catherine with the prosperity that he had brought to her subjects, he is said to have built handsome fake villages all along the route of her tour through southern Russia in 1787. Historians doubt this tale, which they blame on malicious court gossip, yet there is something about the idea of “Potemkin villages” that lingers in the memory as a symbol of political craft.
 
Let us therefore salute Anthony B. Gliedman, New York City commissioner of housing preservation and development, who is carrying on a program worthy of Potemkin at his most imaginative.
(...)
We don’t want anybody to think we’re doing this instead of rebuilding,” the commissioner told the New York Times. “But that will take years and require hundreds of millions of dollars. And while we’re waiting, we want people to know that we still care. We want people to feel good about their neighborhood. Morale is very real. Perception is reality.”
     
Google Books 
Probing Leviathan:
An investigation of government in the economy
By George Lermer, Thomas J. Courchene, et al.
Vancouver, BC, Canada: Fraser Institute
1984
Pg. 96:
In politics, perception is reality.
 
Google Books
Straight from the heart
By Jean Chrétien
Toronto, Ont., Canada: Key Porter Books
1985
Pg. 81:
At least he seemed to have grown and changed, and in politics perception is everything.
 
Google Books
The Rainmaker:
A passion for politics
By Keith Davey
Toronto, Canada: Stoddart
1986
Pg. 57:
In politics, perception is reality.
KEITH DAVEY
   
31 March 1986, Frederick (MD) News-Post, “The mayor who would be governor” by Roy Meachum, pg. A6, col. 2:
The truth matters little in political campaigns: perception is everything.
 
6 August 1986, Paris (TX) News, “Looking back at the Chapman-Hargett race” by Phillip Swann, pg. 6A, col. 4:
But for the moment it seems that the Chapman victory has stemmed the tide for the Democratic Party.
   
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“So, what are the boys saying?”: an inside look at Brian Mulroney in power
By Michel Gratton
Toronto: McGraw-Hill Ryerson
1987
Pg. 70:
But as the legendary Liberal strategist, Keith Davey, has pointed out, in politics perception is everything, and the immovable perception The Boss created was one of an inward-looking, combative perfectionist.
 
Google Books
Stewards of the State:
The governors of Michigan
By George Weeks
Ann Arbor, MI: Historical Society of Michigan
1987
Pg. 154:
Unfortunately, perception is everything in politics. Political careers are built on images.
   
Google Books
June 1988, Orange Coast Magazine (CA), pg. 69, col. 1:
In politics, perception is everything, and a perceived conflict is as good as a genuine one.
       
Google Books
New perspectives in American politics
By Lucius Jefferson Barker
New Brunswick, NJ: [Published for the National Conference of Black Political Scientists by] Transaction Publishers
1989
Pg. 150:
Perception is reality in politics, and questions then arose in a continuing debate as to why Jackson ran, a theme that may be understated in the analysis.
 
19 September 1990, Frderick (TX) News-Post, pg. A10, col. 3:
Relying on the old adage that in politics public perception is everything, Mr. Schaefer is substituting serious campaigning for public relations gimmicks.
 
“Perception is everything in this business and the perception is there that we stopped what appeared to be a Republican onslaught,” Chapman said.
 
Counterspin
In Politics - Perception is Everything
By wwillard ~ June 2nd, 2009 @ 8:37 pm
I had a little chuckle while reading Andrew Prescott’s letter (to the Guelph Mercury Editor June 2, 2009) regarding the current situation in federal politics. It always amazes me how much perception comes into play.
     
The Courier-Mail (Sydney, Australia)
Government secret talks blunder
January 27, 2010 12:00am
CLICHES often evolve because they are innately true. Certainly that is the case with the age-old axiom that in politics perception is everything.