Too bad that there were no checks in place to determine who is actually contributing. For that reason, many non-citizens were able to contribute, some from questionable places, and even Osama ibn Laden had posthumously donated, receiving congratulation later from Barrack's wife thanking him for his donation [1].
Since Romney was rejecting contributions that could not be confirmed as of where they came from, this race in terms of fund-rising was skewed from a get-go. Imagine a marathon where everyone runs on their feet and you -- against the rules -- are using a bicycle. Guess who's gonna win?
[1] http://www.wnd.com/2012/10/obama-accepts-osama-bin-laden-don...
For those who hate googling:
http://www.washingtonpost.com/wp-dyn/content/article/2008/10...
http://townhall.com/tipsheet/katiepavlich/2012/10/08/exposin...
http://www.thecuttingedgenews.com/index.php?article=76534...