Could it be the spoiler ticket of 2012? Fox News is excited about the emerging links between progressives and libertarians, namely the growing alliance between Green Party candidate Ralph Nader on the left and Republican Texas Congressman Rep. Ron Paul.
The far left and far right have long been frustrated that bipartisan politics means a consensus around doing the will of big business. On Fox, Tea Party hero Paul said "They talk about we need more bipartisanship, and I say we have too much bipartisanship because the bipartisanship we have here in Washington endorses corporatism."
A political alliance between the far ends of the U.S. political spectrum on things like military spending, Wall Street reform, and civil liberties could give a more unified voice of opposition to business as usual, especially as Obama bounds to the center. On the other hand, such alliances are always uneasy, to say the least, often based on the philosophy of "the enemy of my enemy is my friend." That tends to be a strategy for noise, not government.
After the WTO demonstrations in Seattle in 1999, some observers had hopes that opposition to globalization would bring labor and greens together in a potent "Teamsters and Turtles" alliance, but that fizzled. During the run up to the Iraq War, some of the best anti-war screeds were written by far-right conservatives like Paul and Pat Buchanan. There's a conservative economic populism that argues against empire, but also slips into nativism and anti-semitism when it rails about Jewish bankers. Too, there are serious differences between progressives, libertarians, and the far, far right on the role and scope of government.
Still, fringe alliances can have an impact for better or worse. Certainly Ross Perot's 1992 populist campaign helped get Bill Clinton elected by drawing votes away from George H. W. Bush, while some believe Ralph Nader's efforts in 2000 hurt Al Gore in what turned out to be the key state of Florida, not to mention the Pat Buchanan-butterfly ballot confusion. But even apart from presidential politics, it can serve to ratchet up pressure on issues and force politicians to take stands. Paul-Nader could force into the open splits between Tea Partiers and mainstream Republicans, for example.
While Nader's leftism seems to have lost a lot of its juice, the Tea Partiers and libertarians appear to have grassroots energy. Certainly that showed during the 2010 mid-terms and Paul's 2008 campaign, which was fueled by techies. Combine that with some percentage of anti-war liberals who are fed-up with Obama and you might, at the very least, see some issues (overseas military base closures, how the Fed operates, government surveillance) get some more airtime. You might also see both parties worry about their vulnerabilities on the fringes in 2012. History does show that sometimes, tiny percentages can make big differences.