Spam and advertising

Two vaguely noteworthy bits of internet advertising recently:

• Hoping to undermine my marriage, some spammer told me to "Search for Your Soulmate" on the day of my tenth wedding anniversary. Hey, fake-eHarmony: knock it off!
• Just how much does Google know about me, anyway? When my NoScript extension for Firefox[1] was updated this morning, the "What's new" page showed an ad for today's primary election here in Michigan. Ok, fine, they know my IP address is in the state. But this ad specifically invited me to "vote across the aisle" for a Republican gubernatorial candidate. How exactly does Google Ads know I'm a Democrat? I mean, I wouldn't be surprised if Google could in fact deduce that to fairly high probability, but is that actually what's happening here? (Does Google offer political affiliation targeting as an explicit option?) Or is this more likely just a gamble that NoScript users lean Democratic?

[1] Use it! Even in its unobtrusive "default allow" mode, it's great protection.