National Institute on Money in State Politics.
Available online.
"While voters may have the final say on ballot measures when they vote “yea” or “nea” at the ballot box, they have little to do with the funding of those measures. In 2006, only 23 percent of the $648 million raised to support or oppose ballot measures came from individuals... The 2006 election also saw a jump in the number of measures faced by voters: 219 measures appeared in 37 states, almost double the 111 measures in 28 states in 2004."
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