Is it possible to have a Google Analytics tracking event on Tumblr's Follow button?

Is there a way to hack a Tumblr theme to put a Google Analytics _trackEventI() function on the Tumblr Follow button? This would allow users to analyze where people are coming from when they click follow, wh开发者_StackOverflow中文版at pages they clicked follow on, demographics of people who followed, etc.

If you control the code that displays it, or if the code is iframed onto your site but the iframe content is hosted on your domain then yes, it is possible. But if it is iframed onto your page and the iframed content is not on your domain then no, you cannot add tracking to it.