RICHMOND, Va. (CBSDC/AP) — Tim Kaine effectively clenched the Democratic 2012 U.S. Senate nomination by being the lone Democrat to submit qualifying petitions.

Four Republicans, however, filed petitions bearing voter signatures in hopes of qualifying for the June 12 primary, heralding two hard months of campaigning for front runner George Allen.

The former Virginia Governor Kaine submitted more than 30,000 signatures on petitions delivered to the State Board of Elections.

Allen tendered the most signatures of any Republican, nearly 27,000. Tea party leader Jamie Radtke presented 21,552, state legislator Bob Marshall submitted 17,133, and Chesapeake clergyman E.W. Jackson gathered 11,188.

Both parties expect to validate the signatures on Friday.

To qualify for the primary ballot, candidates had to submit petitions bearing 10,000 registered voters’ signatures, including at least 400 from each of Virginia’s U.S. House districts.

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