For almost all my life, I have been a "professional Democrat," as well as a strong believer in our dual-party system, with a range of philosophies under "two big tents." As a 9-year-old, I wore an Adlai Stevenson for president button to the fourth grade. I wanted to "complete the New Deal" as a 1960's left-liberal teenager. At 36, I became press spokesman for the oldest continuing party committee in the world, the Democratic National Committee (1983-87.) And since then, I have run a program to teach college journalists about "practical politics," preaching that having just two parties helps simplify electoral and governing choices.

With that partisan pedigree, I am about to become an apostate. I am going to do what I think the founder of the Democratic Party, the classical liberal Thomas Jefferson, might consider doing this year. I am going to vote for former Republican New Mexico Gov. Gary Johnson, now the Libertarian Party candidate for president.

I don't intend to change my registration. I'm still a Democrat. But I'm a small "l" libertarian Democrat, who wants to teach fellow Democrats that 21st century libertarians are not a bunch of selfish, Ayn Rand-style, greedy capitalists. Among the three issue frames of politics—economy, social, and foreign—most rank-and-file Democrats share much in common with modern libertarians. Most libertarians want to keep government out of our bedrooms, away from our bodies, and out of the backyards of the rest of the world. On the economy, while we are for limited spending, taxes, and regulation, we favor free markets—not oligarchic capitalism that uses government to re-distribute tax revenue to the military-industrial-congressional-media complex, the behemoth pharmaceutical companies, or other lobbyists along Washington's K Street who seek benefits from government and regulations that put competitors at disadvantage.

Why would I abandon the candidate for whom I had great hopes for change in 2008, a president from my own home state of Illinois, Barack Obama? In fact, I even made a libertarian case for Obama in 2008 at Reason.com—which turned out to be hoping against nothing but hope.

For me, that hope turned to despair when President Obama ramped up another hideous elective war, putting tens of thousands of young men and women in harm's way in Afghanistan; rammed through a taxpayer and deficit-funded corporate welfare program for drug and insurance companies, in the guise of health care reform; and reneged on promises to slow prosecutions in the assault on personal freedom, the violence-creating neo-Prohibition known as the war on drugs.

While some Democrats may avert their eyes from that record, this libertarian Democrat is going to vote on principle. Gov. Gary Johnson balanced New Mexico's budget all 8 years he served; he pledges to end the insanity in Afghanistan immediately; he is committed to legalizing drugs, to ending the government-induced black market that drives up profits and causes Mexican cartels to murder thousands, like the Al Capone murder and mayhem created by alcohol Prohibition. And he wants to end handouts to corporations that see the U.S. Treasury as a giant ATM, stocked with cash by both Democrats and Republicans in Congress.

I have been a slave to political pragmatism during my four decades in these 10 square miles surrounded by reality known as Washington, D.C. But this year, I encourage my Jeffersonian, classical liberal friends, in each party and neither, to send a simple message to both my party and the Republicans, in the form of votes for Gary Johnson.

Just one word, that message fits easily on a bumper sticker. Liberty.

Director of the Washington Center for Politics & Journalism, Terry Michael is a former press secretary for the Democratic National Committee. He writes at his libertarian Democrat web site, www.terrymichael.net.