Last fall, Oregon Rep. Peter DeFazio was the subject of a political ad paid for by the Concerned Taxpayers of America — which turned out to be a million-dollar front group financed by just two men. Read more about that ad, and how DeFazio followed the money. Jonathan Ernst/Getty Images hide caption

itoggle caption Jonathan Ernst/Getty Images

Former House Speaker Newt Gingrich, speaking at a news conference Thursday in Atlanta, says he is launching a website to explore a run for president. Mike Stewart/AP hide caption

itoggle caption Mike Stewart/AP

Demonstrators gathered outside the Ohio Statehouse last week to protest Senate Bill 5, which would have banned collective bargaining for state workers. Unions say legislation being pushed by Republican governors nationwide is an attack on their very existence. Jay LaPrete/AP hide caption

itoggle caption Jay LaPrete/AP

The Koch Industries Inc. headquarters in Wichita, Kan. LARRY W. SMITH/ASSOCIATED PRESS hide caption

itoggle caption LARRY W. SMITH/ASSOCIATED PRESS

President Obama, shown answering questions during a news conference Tuesday, is expected to hit the billion-dollar mark in fundraising for his re-election bid. His Republican opponent may raise that much as well. Evan Vucci/AP hide caption

itoggle caption Evan Vucci/AP

Rep. Charles Rangel (D-NY) is likely to learn Thursday whether the House of Representatives will vote to censure him for ethics violations. Mark Wilson/Getty Images hide caption

itoggle caption Mark Wilson/Getty Images

Rep. Charles Rangel, shown leaving his office for a vote at the Capitol in July, is accused of 13 ethics violations. Among them: that he lied about his finances in his personal disclosure filings and dodged taxes on rental income from a vacation home in the Dominican Republic. Alex Wong/Getty Images hide caption

itoggle caption Alex Wong/Getty Images

Sen. Jim DeMint (R-SC), shown speaking to the Values Voter Summit in Washington in September, has new clout in the Republican Party after backing conservative candidates in the midterm elections. Jacquelyn Martin/AP hide caption

itoggle caption Jacquelyn Martin/AP

Sen. Russ Feingold (D-WI) makes his concession speech to his supporters Tuesday in Middleton, Wis., after losing to Republican challenger Ron Johnson for the Wisconsin U.S. Senate seat. Joe Koshollek/AP hide caption

itoggle caption Joe Koshollek/AP

The 60 Plus Association attacks U.S. Rep. Allen Boyd in one of its ads. The group is part of a tightly woven network behind a slew of campaign ads this fall. hide caption

itoggle caption