Many, many thanks to deadrose for information about Washington State's now sadly extinct Owl Party. As you can read in the link, the state changed the election laws to prevent small parties from getting on the ballot, a law that was ultimately upheld by the US Supreme Court.
However, (and this is a pretty big however) in 2004, the legislature enacted the "Pick-a-party" primary. Now this new primary system only applies to parties that received at least 5% of the vote in the previous Presidential election. I'll let the Washington Secretary of State speak for the rest:
Under the pick-a-party system, minor party and independent candidates do not appear on primary ballots but advance directly to the general election. To appear on the general election ballot, minor party and independent candidates must be nominated at a convention and have either 100 or 1,000 signatures of registered voters, depending on the office.
The PDF document can be found here. Based on this information, I'm pretty sure a new party could run a full slate of candidates for statewide office in 2008. Who's interested? Wet blankets need not apply.
I note that we already have three possible planks for our platform (per this entry). We're going to need more.