Minify Html output of ASP.NET Application

Question

What are the ways by which we can reduce the size of the HTML Response sent by an asp.net application?

I am using Controls which are not owned by me and it produces

Answer 1

The accepted answer does not work with MVC 4, so here is a similar lib that minifies at build-time https://github.com/jitbit/HtmlOptimizerMvc4