P. J. O’Rourke is an author known for political satire. He wrote in Parliament of Whores: A Lone Humorist Attempts to Explain the Entire U.S Government (1991):
 
“Politicians are interested in people. Not that this is always a virtue. Fleas are interested in dogs”
 
In other words, politicians are interested in people only for how the people can help the politicians. O’Rourke’s observation has been frequently cited.
 
 
Wikipedia: P. J. O’Rourke
Patrick Jake “P. J.” O’Rourke (born November 14, 1947) is an American political satirist, journalist, writer, and author. O’Rourke is the H. L. Mencken Research Fellow at the Cato Institute and is a regular correspondent for The Atlantic Monthly, The American Spectator, and The Weekly Standard, and frequent panelist on National Public Radio’s game show Wait Wait… Don’t Tell Me!.
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According to a 60 Minutes profile, he is also the most quoted living man in The Penguin Dictionary of Modern Humorous Quotations.
 
Google Books
Parliament of Whores:
A Lone Humorist Attempts to Explain the Entire U.S Government
By P. J. O’Rourke
New York, NY: Atlantic Monthly Press
1991
Pg. 58:
The congressman was interested in the volunteer firemen. Politicians are interested in people. Not that this is always a virtue. Fleas are interested in dogs.
 
Google News Archive
18 August 1991, The News and Courier (Charleston, SC), “Laying cards on the table” by Schuyler Kropf, pg. 7-F, cols. 5-6:
(A book review of Parliament of Whores—ed.)
He also points out what South Carolina recently really learned about politicians. “Politicians are interested in people,” he writes, the same way “fleas are interested in dogs.”
 
Google Books
Return of the Portable Curmudgeon
Compiled and edited by Jon Winokur
New York, NY: Plume
1995, ©1992
Pg. 242:
Politicians are interested in people. Not that this is always a virtue. Fleas are interested in dogs.
P. J. O’ROURKE
 
Google Books
From Hope to Higher Ground:
My Vision for Restoring America’s Greatness
By Mike Huckabee
New York, NY: Center Street
2008, ©2007
Pg. 100:
Some of the more potent O’Rourkeisms are:
 
. Politicians are interested in people; not that this is always a virtue, fleas are interested in dogs.
 
Milford, CT Dyslexic Environmental Blogger
22.10.12
OBSERVATIONS ON POLITICIANS “Politicians are interested in people. Not that this is always a virtue. Fleas are interested in dogs.”