Twitter is more than another version of Google ads. The right way to fundraise for any cause is to realize that Twitter is made up of people, not messages with links that point to your site. Instead of trying to post messages that users click on, you should build up a large group of engaged supporters who will help spread your message. Do not think of them as just donors who click, donate, and then stop. If handled correctly, people on Twitter will become highly effective fundraisers for you.