Ralph Nader, the independent presidential candidate, filed a 64-page brief Friday asking the Pennsylvania Supreme Court to restore his name to the state's November presidential ballot. The Pennsylvania Commonwealth Court invalidated his nominating petition Wednesday; read the opinion and order here [PDF]. In Friday's brief Nader argued that the Commonwealth Court erred in its decision by ruling that petition signatories needed to be registered voters rather than qualified electors. Nader has also requested that the Department of State refrain from certifying the presidential ballot until the Pennsylvania Supreme Court rules on his challenge, which should be early next week. AP has more.