Election 2016 by the numbers

Related: By the numbers: a 2015 money-in-politics index

This story is part of Buying of the President 2016. Tracking the candidates, political committees and nonprofits that are making this presidential election the most expensive in history. Click here to read more stories in this investigation.

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This story is part of Buying of the President 2016. Tracking the candidates, political committees and nonprofits that are making this presidential election the most expensive in history. Click here to read more stories in this investigation.

Copyright 2015 The Center for Public Integrity. This story was published by The Center for Public Integrity, a nonprofit, nonpartisan investigative news organization in Washington, D.C.