I gave blood yesterday. My goal is to get to a gallon and I've got a few pints to go.
If you've never given blood, I would encourage you to do so. It only takes about a half an hour with most of that time being subjected to questions like, Have you ever shared a needle with someone named CoCo? Have you ever had anal sex with someone named A-train?
Regardless, it's a good cause and it doesn't cost you anything; something you'd think would attract liberals.
Speaking of which, I think I know why conservatives give more blood than liberals. Because, unlike liberals they can actually answer no to the questions above.