Act Blue

You may be familiar with them as a collector of candidate contributions, but they are now equipped to handle compliance reporting in Oregon and have made their services available to any county party (or Democratic candidate) that wants to use them.

In fact, they have already set up donation pages for every county party in Oregon:
http://resources.dpo.org/y/kysz (this is a "tinyurl" to a long actblue url.)

I have attached a PDF brochure that describes what they offer.

In essence, they are a PAC that aggregates contributions for political committees.
Donors make contributions to ActBlue that are designated for particular committees.
ActBlue aggregates them, deducts a minor processing fee, and sends a check out to the committee each week.  As a committee, you do not need to have your own merchant account.

Since Act Blue doesn't cost a thing until it is used (and then only a
small processing fee), it makes sense to take advantage of it. After
all, millions of people around the country are visiting Act Blue and
making donations.

They are working on (or may have already) event signup tools as well. If you contact them you can customize your donation page. They can process recurring contributions as well.

There is no more cost-effective way for county parties to use on-line technology to collect contributions.