Roxanne Weber (left) rallies in support of a voter-approved government ethics overhaul in front of the South Dakota Capitol in Pierre last month. Republican Gov. Dennis Daugaard said he supports efforts to repeal and replace the initiative.
The state capitol building in Jefferson City, Missouri. Voters will vote on a ballot measure that would end the state's current practice of allowing unlimited campaign contributions and reimpose limits of $2,600 per candidate.
Education Images/UIG via Getty Images
Conservative donor David Koch in a 2013 file photo. The political network he and his brother, Charles, have created is not backing Donald Trump's presidential bid this year.
Phelan M. Ebenhack/AP
Donald Trump began his campaign for president saying he would pay for it out of his own pocket. Now, he is accepting big donations and has a superPAC working on his behalf.
John Sommers II/Getty Images
Republican presidential candidate Donald Trump in Dallas on June 16, 2016. Trump's campaign is struggling to raise money to finance his bid against Democrat Hillary Clinton.
Ron Jenkins/Getty Images
Democratic presidential candidate Bernie Sanders speaks during a rally in Washington, D.C., on June 9. Although he didn't win the nomination, Sanders' grass-roots fundraising has broken records.
Alex Wong/Getty Images