Making donations to ActBlue and others [View all]

I get lots of emails from ActBlue and other organizations asking for donations, and I donate regularly when I can. But I'm curious about all the emails offering to triple or quadruple, for example, my donation. How does this work? I can't find any information on the ActBlue web site.

I'm always on my guard against spoofing and phishing and don't like clicking on links in emails. I prefer to go directly to the web site to make a donation, but once there, I don't see any options to have my donation multiplied.

Can someone shed some light on why this is? Any advice is appreciated.