By not accepting public finance contributions during the presidential campaign, Barack Obama helped his cause because ___ he was limited on how much money he could raise.
Barack Obama raised around $153 million in September, 2008, this was a record in the campaign finance comparing with others candidates in history. He was even criticized for raising so much money that could cause in future fundraising abuses. If he applied for the public finance contributions he could not have raised so much money, because the public funds had rules which set a limit of spending to the grant you receive and do not allow you to take private contributions for your campaign.