No. NationBuilder will never put ads up on your website.
However, you are free to put your own ads up on your website and earn money from them. Currently, none of our official themes allow for ads, so if you wanted to do this you would have to create your own theme in the custom theme creator.
Ian Patrick Hines commented 2013-09-19 11:22:54 -0700Ben — NationBuilder will never add advertisements to your site. If you’re seeing ads there — and did not add them yourself — please email firstname.lastname@example.org your organizer will help you figure out how they got there and help you remove them.
Ben Murray commented 2013-09-19 03:21:41 -0700Why am I now seeing adverts at the bottom of my sites?