Independent expenditures in US House and Senate
$0
$50m
$100m
$150m
$200m
$250m
$300m
$350m
$400m
$450m
$500m
$550m
$600m
$650m
2008
2009
2010
2011
2012
2013
2014
2015
2016
U.S. House
U.S. Senate