Not a βtrueβ solution, but the work around I found that if I applied my class to the same div as the large text, I would get the desired result.
.theme.bigtext{ font-family:Arial }
It feels really hacked, because in the project I'm working on, I need to perform a class switch and what is not in javascript, but it does its job.
http://jsfiddle.net/pF5bQ/7/
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