OK, maybe that is premature since voting won't begin for a few hours, but I am on the primary ballot in Washington, as the Republican precinct committee officer for my local voting precinct, and I am unopposed. (If I were opposed, I likely wouldn't run at all
The organization of the state party works like this: the state party consists of committeepeople from each county, elected by the county central committee. The county central committee consists of the PCOs, which are elected by the voters of that precinct on the primary ballot. So the PCO is the basic unit of the state party. The party is comprised of them, and their function is, beyond that, to support the party at the precinct level: getting the vote out, supporting candidates, etc.
I'm PCO right now, because I was appointed to fill the vacancy. At least, I think I am. I was told I was, and I filled out all the paperwork, though I never saw anything that proved it, and I saw some list of PCOs as of August 2004 and I wasn't on it. Not that I really care either way.
In Massachusetts, I was also on the primary ballot, in 2000. Instead of per-precinct PCOs and county committees, we had town committees for each party, with the towns getting a number seats by population. There were 35 people on the ballot for that position, which made coming in 35th place seem not so bad. From there I was chosen as a delegate to the state convention in 2002, though I was not able to attend.
Some have asked how I got involved. Basically, I just showed up. I went to the caucuses and conventions and met people and eventually paid a $1 filing fee to get on the ballot. Don't be discouraged from getting involved: like much of life, most of it is just showing up.