In the 1974 congressional elections, total spending on Senate and House races came to only $77 million. According to the Center for Responsive Politics, by 2008 the figure was $1.36 billion, with lobbyists providing a significant amount.
The accuracy of the second sentence depends on the meaning of "significant." The Center for Responsive Politics calculates that lobbyists gave $36.6 million in 2008 -- a fair sum, but only 2.7 percent of total spending.
