I did check with them and have donated to both web and by mail (I will only donate up to $50 online, anything higher I send my snail mail). Notice on the online page it has the same mail address for donations as the general one you cited. I really hope this poll is wrong, but something very strange is happening in Arizona, with Obama within 2%, and Carmona and Flake changing leads every few days. Soros and the unions are spending a fortune trying to turn Arizona blue.
I agree, someone has been pouring TONS of money into the Arizona elections for the past month. Most of the money against Arpaio and Flake.