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Either your argument is faulty or opensecrets.org is supplying false information. According to opensecrets.org, Obama's PAC contributions is $25. Furthermore, By your estimate, the only non-PAC contributions would only come from the unemployed or from contributions less than $200. Also, the unemployed contributer would have to be a single person since a married unemployed person would have their contributions counted towards their spouse's employer.
But honestly, according to opensecrets.org, most PAC contributions target members running for the Senate. Opensecrets.org states that in presidential elections only about 1% of total the contributions come from PACs. Even Hillary's PAC contributions is less than a million which is less than 1% of total.