We go through this every four years.

The two major parties choose their presidential candidates. But that doesn’t stop a slew of lesser-known third parties from trying to crash the big party, with a vow to dramatically reshape the political landscape.

And how does it turn out? Some underdogs actually make it on the ballot. Rarely does one make it to a presidential debate (Ross Perot, yes; Pat Buchanan and Ralph Nader, no), where 15% in the polls is the price of admission. A select few, historically, actually succeed in impacting the November election.

And the rest of the bit players?

"Alex, I’ll take “Forgotten Also-Rans” for $200, please . . ."

The 2012 election, it turns out, is more of the same (here’s a list of all third-party candidates who’ve toyed with the idea of running). It began with talk of a third-party outfit, Americans Elect, radically changing the process by holding a first-of-its-kind national online party. The group talked boldly of qualifying for the ballot in all 50 states, and even spent $35 million to get on the ballot in some 29 states.

The problem was: lots of bucks, but no Buck Rogers. Absent a quality candidate, the online movement fizzled earlier this year.

Write it down: here’s one of the worst prophecies of the 2012 election, courtesy of The New York Times’ Thomas Friedman from July of last year:

“Write it down: Americans Elect. What Amazon.com did to books, what the blogosphere did to newspapers, what the iPod did to music, what drugstore.com did to pharmacies, Americans Elect plans to do to the two-party duopoly that has dominated American political life — remove the barriers to real competition, flatten the incumbents and let the people in.”

Uh-huh.

In this Olympic year, it’s worth remembering those third-party candidacies that medalled in electoral mischief. That would include:

  • Gold Medal: Theodore Roosevelt and the Bull Moose Party. TR raked in 27% of the vote and 88 electoral votes in 1912 (to just 8 electoral votes for the incumbent GOP President William Howard Taft), handing the election to Woodrow Wilson.
  • Silver Medal: Perot, whose entry, withdrawal and subsequent re-entry to the 1992 election (he’d end up with 18.91% of the vote, but nada in the Electoral College) opened the door to a Democratic victory (Clinton, like Wilson getting 43% of the vote).
  • Bronze Medal: A tie between George Wallace (carried 5 Deep South states in 1968 and threatened to push the contest into the U.S. House of Representatives) and Nader (nothing to show in the way of states or electoral votes, but his presence in New Hampshire and Florida may or may not have cost Al Gore the 2000 election).

In 2012, three third-party candidates bear watching – two, because there’s a remote chance of impacting the swing states; the third, simply because it’s hard to ignore a train wreck. And that would be the comedienne Roseanne Barr, who’s running on the Peace and Freedom Party ticket with the anti-war activist Cindy Sheehan, whom she met via filmmaker Michael Moore (Peace and Freedom being the party“socialism, democracy, ecology, feminism, and racial equality”).

No joke.

In this interview, the former sitcom star (and noted butcher of the national anthem) says America has been “bamboozled and hoodwinked” . . . government is “owned by bankers” . . .  “Americans have been bull-----ed into forgetting that war does not mean freedom . . . When I’m president, I’m gonna outlaw bull---.”

If elected, Barr says she’d cut defense spending, tax the rich and legalize marijuana.

Which takes us to the second third-partier worth watching: Gary Johnson, the former New Mexico governor and current Libertarian Party standard-bearer (party slogan: minimum government, maximum freedom”). Johnson, like Roseanne, favors marijuana legalization – which, of course, has branded his campaign as having gone to pot.

That said, Johnson’s candidacy is more than smoke and mirrors. In a close election, the Libertarian presence could cause mischief in the swing states. Take Colorado, for example. A recent survey by Democratic-leaning Public Policy Polling gives the state to President Obama, 49%-43%. But add Johnson to the mix (he gets 7%, according to PPP) and the President’s lead over Mitt Romney shrinks to 46%-42% – again, the wild-card nature of the Libertarian vote in that there’s no certain rule as to which major majority suffers more.

Of course, Romney could lose Colorado and still win the election. That’s far less likely if he comes up short in Virginia (most Romney victory scenarios begin with the GOP nominee recapturing Indiana, North Carolina and Virginia), another state where third-party influence could come into play.

The problem for Romney in the Old Dominion: Virgil Goode, the former Virginia congressman currently headlining the decidedly conservative Constitution Party ticket. That is, if Goode gets on the ballot: he needs 10,000 signatures by August 24 to qualify for the Virginia ballot (he aims to hand in 20,000). And, if he can survive an investigation into “suspected petition fraud.”

Goode and the Constitution Party are already on the ballot in 17 states. But it’s the potential of that 18thstate – Virginia – that has both the Romney and Obama worrying (potentially, he could pick off both steadfast conservatives who’d vote for Romney, as well as lifelong Democrats who normally would tow the party line but like Goode from his twelve years in Congress).

In other words, it’s no laughing matter – unless you’re thinking about Roseanne Barr.

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