The Republicans and Democrats who wrote the rules for candidates to get on the ballot in Pennsylvania ensured that in virtually all cases the choices would be limited to two, denying voters the sort of selection they get in a supermarket pizza aisle.

White or with sauce? Super-size or personal pan? Frozen or fresh? Meat, veggie or plain? Yum, the endless alternatives! Wouldn't it be nice to have that many choices of candidates? Not a pizza's chance in a frat house of that happening, however, in Pennsylvania.

The way it works is Republican and Democratic candidates for statewide office must collect 2,000 signatures on petitions to get on the primary ballot. Registered members of the major parties then vote to determine which candidates should advance to the fall ballot. Pennsylvania excludes candidates from other parties -- like Green, Libertarian and Constitution -- from the primary.

To get on the November ballot, their candidates for statewide office -- governor, U.S. senator and so on -- must gather thousands more signatures than are required of the majority-party candidates. The number is 2 percent of the total votes cast for the contestant who got the most ballots in the last statewide election.

This year, that number is 67,070. So while U.S. Senate candidates Democrat Bob Casey and Republican Rick Santorum needed to find only 2,000 registered voters to sign their nominating petitions, Green Party contestant Carl Romanelli had to get 33 times that many.

Mr. Romanelli was knocked off the ballot by Commonwealth Court, and properly so, for being short by 9,000 signatures. He could return, however, if he wins an appeal before the state Supreme Court.

His candidacy gets no sympathy from us because his petition drive was funded in part by Republican donors who see the Green candidate taking votes from Mr. Casey. What concerns us, however, are the disparate ballot requirements in state law for major-party and minor-party candidates.

The double standard for Republicans and Libertarians, Democrats and Greens, would seem to violate the state constitutional provision that says all laws regulating elections shall be uniform. The lame excuse given to justify the stiffer requirements for minority parties is that weaker ones would result in too many candidates cluttering up the ballot.

In other words, Pennsylvania's politicians feel it is important to limit voters' choices to pizza with pepperoni and pizza with sausage. That is not what's supposed to happen in a democracy. In a true democracy, a variety of ideas and candidates is encouraged.

The signature requirement should be the same for majority and minority parties, and the law should set it somewhere around 10,000, the number a federal judge in Arkansas recently determined as sufficient for third-party candidates in that state. Choice in a democracy, just like in a grocery, is good.