Before the 2010 U.S. midterm elections, Joe Walsh was a two-time political loser who almost no one - excluding maybe his family and close friends - thought would win a seat in Congress.

Now the 49-year-old former American history professor and investment banker is among a group of first-term House Republican lawmakers who, arguably, wield more power over America's debt crisis than the president of the United States.

Swept into office last November on a wave of support from Tea Party conservatives, Walsh, who represents Illinois' 8th district, is one of 87 GOP freshmen whose opposition to a compromise over raising America's debt ceiling risks pushing the U.S. government into default.

Call them uncompromising, or call them principled, this much is undisputed about the Republican newcomers: Without their backing, the Republican-controlled House of Representatives will have extraordinary difficulty getting the necessary 218 votes to pass bipartisan debt legislation before the U.S. reaches its $14.3 trillion borrowing limit on Aug. 2....