It happened earlier this month, but it's worth noting: Gary Johnson won a nine-week legal war for the right to appear on Pennsylvania's ballot. His Libertarians had put in more than enough signatures, more than 20,601, to keep Johnson on. (Major-party candidates only need 2,000 signatures.) His opponents were, mostly, Republicans. And those Republicans managed to clear one other candidate off the list:
The Constitution Party withdrew its presidential candidate, Virgil Goode, from the state ballot on Tuesday. The party submitted 35,000 signatures, but state law would have required them to cover the cost of legal fees if the Republicans had been able to successfully challenge enough of the signatures to bring them under the state threshold.
Jim Clymer, a lawyer and state treasurer for the Pennsylvania Constitution Party, said those fees could have easily exceeded $100,000.
This stuff matters. In 2000, Ralph Nader's campaign got ballot access in Pennsylvania and won 103,392 votes. Four years later, John Kerry narrowly but decisively defeated George W. Bush in Pennsylvania, by 144,248 votes. Nader wasn't on that ballot. Democrats successfully challenged his signatures and kept him off, part of a yearlong effort by state parties and the national Democrats that reduced Nader to a yowling protest candidate begging his opponents to "call off your dogs."
Republicans learned the lesson insasmuch as they could. In 2006, when it was clear that Bob Casey would have a huge advantage in a two-candidate race, Rick Santorum directed supporters to aid Carl Romanelli, the Green Party's U.S. Senate candidate. They did, and Romanelli appeared to make the ballot, but too many of his signatures were bogus, and ironically, too much of that new red-green money was used in ways that violated campaign finance law.
There's no evidence that Democrats helped either the Johnson nor Goode campaigns in Pennsylvania. It wasn't in their interest to; who knows where the drone-hating college student goes if he has a chance to back someone besides Obama? Democrats have largely ignored Jill Stein, the current Green candidate -- I figure that's because she's 1) completely uninteresting as a spoiler and 2) challenging her ballot papers would queer the Democrats base-galvanizing message of registering voters. This stuff takes time and resources, and the threat of white liberal dilletentes voting for Greens isn't as big as the threat of failing to register voters in Bucks County or Philadelphia.
But this sideshow is one of the best examples at how desparate the parties can get in swing states. And there's no on-the-other-hand'ing about this. Some of the Republicans now embroiled in voter registration scandals cut their teeth on the campaigns to get signatures for candidates who could hurt Democrats.