Mary Jo Pitzl

The Republic | azcentral.com

Frank Tamburri will not appear on this year's ballot as a Libertarian candidate for U.S. Senate.

Maricopa County Superior Court Judge John Hannah rejected arguments that Libertarians are subjected to unfair requirements for signatures on their nomination papers, and determined the naturopathic doctor lacked the required 3,034 signatures.

However, Tamburri is filing an appeal with the Arizona Supreme Court. If the lower-court ruling holds, there will be a primary only on the Republican ballot. Democrat Ann Kirkpatrick is running unchallenged.

If he's successful, Tamburri would be the sole Libertarian on his party's primary ballot, which means he would be on November ballot as the Libertarian standard-bearer.

Arizona Republican Party Chairman Robert Graham filed the complaint against Tamburri. Republicans suspected Tamburri was recruited by the Democrats to run, figuring he could pull votes away from the GOP nominee in what is expected to be a tough general-election race.

But Tamburri has maintained he is a genuine Libertarian, not a recent recruit to the party ranks. His defense in the petition challenge revolved around what he maintained were unfair signature requirements for minor parties. But Hannah cited a Georgia case in which the U.S. Supreme Court upheld a signature requirement of 5 percent of registered voters in a given party. In Arizona, the requirement is one-quarter of 1 percent of voters — and that can include independents.

Reach the reporter at maryjo.pitzl@arizonarepublic.com and follow her on Twitter, @maryjpitzl.