President Obama walks to the podium at his 2008 nominating convention. Lawmakers are inserting into the spending bill a provision allowing political parties to collect up to $97,200 from each donor to pay for their conventions. Chuck Kennedy,Scott Andrews/AP hide caption

itoggle caption Chuck Kennedy,Scott Andrews/AP

House members and those newly elected to the Legislature gather in the House chamber at the Arkansas state Capitol in Little Rock, Ark. Nov. 7, 2014. Arkansas' legislature is just one of 31 state legislatures in Republican control. Danny Johnston/AP hide caption

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The amount of money spent on Capitol Hill is way more than small change — but the impact of that money is a little murky. Here, the U.S. Capitol is reflected in a fountain full of coins on Election Day this year. Mark Wilson/Getty Images hide caption

itoggle caption Mark Wilson/Getty Images

Republican U.S. Senate candidate Dan Sullivan greets supporters on election night in Anchorage. The as-yet-undecided race between Sullivan and Democratic incumbent Sen. Mark Begich was the hottest in the state. Ted S. Warren/AP hide caption

itoggle caption Ted S. Warren/AP

Tom Steyer recently said in a video that "climate change is not just an important issue, it's the issue. And we need leaders who will take it seriously." Isaac Brekken/Getty Images hide caption

itoggle caption Isaac Brekken/Getty Images

Among outside groups — that is, not candidates or party committees — more than half of this cycle's political ads are financed by secret donors. iStockphoto hide caption

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