From the Philadelphia Bulletin:

When threatened with a legal challenge to the signatures on the nominating petitions, third party candidates do not have the necessary funds to fight back, said Bonita Hoke, executive director of the non-partisan League of Women Voters of Pennsylvania.

“It is all too easy for major party candidates, with access to large sums of money, to successfully challenge the nomination petitions of minor party candidates who may lack the resources needed to defend their candidacy and pay the fines if the challenge is successful,” said Ms.