Two recent cases here locally that I'm aware of, About 3 or 4 years back a woman in Wilkes-Barre collected signatures for a petition to get a vote on the ballot in the city of Wilkes-Barre. The city sued claiming she collected them under false pretenses which may or may not be true, I believe the gist of the cities position was the ballot question would have changed the way government was run but she collected the signatures under the guise of stopping the closing of a firehouse in her neighborhood... which if the ballot was successful would certainly could have an impact on such a decision.
She withdrew the petition a few days or possibly even hours before it was to go before a judge. The city then turned around and successfully sued her in county court and won a judgment for over $11,000 for expenses related to the petition. That decision was reversed at the appellate level and just recently she successfully won a lawsuit for over $60,000 because the city violated her constitutional rights. In her case the slow wheels of justice proved successful to some extent however the question never made it onto the ballot and how many other people will be willing to go through such an ordeal? This is really the primary concern here.
The other case I'm aware of is of Carl Romanelli who is being sued for the costs of litigation by the Democrats after they successfully blocked his nomination petitions. What is really disheartening is there are allegations these cases might have been brought against both Romanelli and Nader on the taxpayers dime as part of the bonusgate scandal in Harrisburg where staffers were doing political work while being paid by the state. There's an interesting op-ed piece here from Ralph Nader because he too was a victim of the same tactics:
This link is broken, either the page no longer exists or there is some other issue like a typo.
If you want to run for public office in Pennsylvania, and you're neither a Republican nor a Democrat, you'd better be prepared to bet the farm. Carl Romanelli learned that lesson the hard way after campaigning for U.S. Senate on the Green Party ticket in 2006.
After a successful challenge to his nomination petitions by Democrats, represented by Thorp, Reed & Armstrong, the Commonwealth Court in Harrisburg charged Romanelli with more than $80,000 in litigation costs. Romanelli, a retired family court officer, says that would "destroy" him financially.
Romanelli's is only the second candidacy in U.S. history to be hit with such costs. My 2004 presidential candidacy was the first. Represented by Reed Smith, Democrats successfully challenged my nomination petitions, and the Commonwealth Court ordered us to pick up the legal bill - once again, more than $80,000.
I don't know about how your view it but it appears to me there has been an epidemic of challenges to candidates over the last few years and many of them being thrown off the ballot on technicalities. 20/20 recently had a piece on this and apparently it is the direct result of campaign finance reform. Only our congress could come up with legislation that was supposed to prevent candidates from rolling over the little guy that does the exact opposite and be able sit on national television and state they voted for bill to stop the ludicrous amount of money given to some candidates.
The gist of it is this the legislation passed a few years back simply shifted many of the direct contributions going to candidates themselves to other places. The new legislation is so convoluted you need an attorney or someone that understands it if you plan to run for office or will run afoul of the law and inevitably be thrown off the ballot. Similar state legislation is being used even on local politicians or small town groups that do not have the resources to file correctly. I know locally there is many people thrown off every year recently.
The 20/20 minutes piece had a few guests all experts on the subject, after explaining how easy it was to stay within the rules the 20/20 interviewer offered to allow them to fill the application out themselves. They all declined.