Ed Koch, the mayor of New York City from 1978-1989, referred to himself as a “liberal with sanity.” Koch meant that he was not a radical liberal or a “loony liberal,” although he refused to call himself a conservative. Koch used the “liberal with sanity” label as early as 1973—several years before he ran for mayor.
 
No other politician has used Koch’s “liberal with sanity” label.
 
 
Wikipedia: Ed Koch
Edward Irving “Ed” Koch (born December 12, 1924; pronounced /ˈkɒtʃ/) was a United States Congressman from 1969 to 1977 and the Mayor of New York City from 1978 to 1989.
 
29 January 1973, New York (NY) Times, “Hogan Is Perturbed Over Whether to Seek a 9th Term” by Frank Lynn, pg. 26:
Mr. Koch, who started his political career as a Greenwich Village reformer and Carmine G. De Sapio’s conqueror, now refers to himself as “a liberal with sanity.”
 
18 April 1975, New York (NY) Times, “Colleagues Consider Koch As Most Effective Member” by Martin Tolchin, pg. 70:
“I think of myself as a liberal with sanity,” Mr. Koch explains. “I believe in liberalism without dogmatism. I try to understand the problems of others, and find a way to accommodate them without compromising my basic point of view.”
     
12 December 1976, New York (NY) Times, “Liberals Refusing to Endorse Goodman” by Frank Lynn, pg. 34:
Mr. Koch says he is trying to raise at least $1 million for his campaign. If he is successful, he hopes to hire David Garth, the campaign and media consultant, and to spend at least $500,000 for a television campaign designed to increase his exposure and to show voters in the outer boroughs that “I’m a liberal with sanity and not a wild-eyed Manhattan radical.” A longtime friend, Bess Myerson, us helping Mr. Koch to raise money.
 
Time magazine
The Nation: Cool Man for a Hot Seat
Monday, Oct. 03, 1977
Introducing Ed Koch, almost certainly New York’s next mayor.
(...)
In addition, Koch had a strategy. A self-proclaimed “liberal with sanity,” he would adjust to the harsh new realities of life in the city by emphasizing management reform and by taking a tough line on fighting crime—including advocating capital punishment. He also became incumbent Mayor Abe Beame’s sternest critic.
     
30 October 1977, New York (NY) Times, pg. 207:
Moreover, Koch goes out of his way, if not to denigrate, then at least to separate himself from, other liberals. “You show me a reformer, and I’ll say, what’s new?” he says, or, “I call myself a liberal with sanity. That drives the exotics up the wall. The exotics—when I first used that word the New Democratic Coalition went crazy,” or, “I’m not knee jerk, never knee jerk,” or, “I support the right to abortion. But the pro-abortionists, they’re so tough. I don’t really like them.” And so on. Koch works hard at this.
 
16 August 1979, New York (NY) Times, “Politicians See a Change in Koch’s Stance and So Does He” by Frank Lynn, pg. B8:
In addition, the Mayor has also disassociated himself from the “antiboss” New Democratic Coalition, with which he was once closely identified, and has implied that many of its members are “crazies”—a favorite term of derogation used by the Democrratic regulars. “I’m a liberal with sanity,” he said in a recent interview.
     
7 November 1980, New York (NY) Times, “D’Amato Assures Koch of Willingness to Help City” by Ronald Smothers, pg. 1:
The Mayor said he liked to think of himself as a “liberal with sanity” rather than a conservative.
 
“I believe that he is a conservative with sanity,” the Mayor said, pointing to Mr. D’Amato.
(Senator-elect Alfonse M. D’Amato, a Republican—ed.)
   
Time magaizne
A Mayor for All Seasons
Monday, Jun. 15, 1981
(...)
The interesting thing about the story, apart from recalling Koch the liberal (as opposed to the “liberal with sanity,” as he describes himself now) is that it reveals an essential part of his makeup.
   
Google Books
Politics
By Ed Koch with William Rauch
New York, NY: Simon & Schuster
1985
Pg. 125:
A Liberal with Sanity