Do you have a web site? Are you willing to use that web site to promote your preferred candidate?
If so, it can be easy (and, so far as I know, the BCRA police won't come knocking at your door -- but don't blame me if they do).
1) Join a "banner exchange" program, such as e-bannerx.com. There are others -- a web search will pull them up. Your choice. Insert their code into your web site's HTML so that you're displaying others' banners and accruing credits to have your own displayed elsewhere.
2) Grab the banner from the bottom of this page, or here. Right click, save as ... you know the drill.
3) Upload the banner and point it at www.badnarik.org. If your banner exchange program lets you do targeting, have the ad displayed on sites likely to have an interested audience.
That's it. Easy enough to do. I just set it up myself and am donating the impressions from my own sites to the cause. No reason that even a few of us can't rack up hundreds of thousands of Badnarik ad impressions over the next two weeks -- so let's do this.