I gave some money to Claire McCaskill in 2012 after the whole Akin blowup. Which put me on the mailing list that she apparently whored out to every politician and PAC she could because now I'm getting emails from Al Franken's campaign asking for money and from Emily's List with the latest "War on Women" updates. Never again.
Honestly, I'd probably be more inclined to contribute if they'd leave me the hell alone afterwards.
Why was that surprising? A list of contacts associated with purchasers of a particular product or viewers of a certain website has been a commodity for a long time. Anyone who engages in economic activity and shares their contact info is likely to get on a list. Charities create lists of donors, too. We may not like who uses the lists we appear on, but they are a fact of modern life.
Contributions to a candidate are also economic activity. The candidate need not even be involved with the creation or distribution of the list. Depending on the state and the size of the donation transparency laws may make the donation public. In some cases candidates use third-party fundraisers who then have the list and may share it with other clients.
As to the question, I donated a little over $3K to political organizations in the 2nd quarter of 2014.