Under-the-radar U.S. Olympic medal contenders

Reese Hoffa competes in the men's shot put during the 2010 USA Outdoor Track & Field Championships at Drake Stadium on June 27, 2010, in Des Moines, Iowa.

Zach Railey competes in the Finn Yellow fleet in race one on the leighton course during day three of the 2011 ISAF Sailing World Championships on Dec. 5, 2011, in Perth, Australia.

Shooter Kim Rhode poses for a portrait during the USOC Media Summit on May 16, 2004, at the Marriott Marquis in New York.

Steven Lopez, right, fights with Mauro Sarmiento, left, of Italy in the quarterfinal of the men's 80 kg taekwondo match during the 2008 Beijing Olympic Games in Beijing on Aug. 22, 2008.

Kristin Armstrong rides towards victory in the elite women's time trial at the 2009 UCI Road World Championships on Sept. 23, 2009, in Mendrisio, Switzerland.

Ellison Brady competes in team archery at the XVI Panamerican Games in Guadalajara, Mexico on Oct. 21, 2011.

Ashton Eaton competes in the men's decathlon pole vault during day two of the 2012 U.S. Olympic Track & Field Team Trials at Hayward Field on June 23, 2012, in Eugene, Ore.

Brittney Reese competes in the women's long jump final at the International Association of Athletics Federations (IAAF) World Championships in Daegu, South Korea on Aug. 28, 2011.

David Boudia dives in the 10m platform final at the 2012 U.S. Olympic Team Trials at the Weyerhaeuser King County Aquatic Center on June 23, 2012, in Federal Way, Wash.

William Claye competes in the men's long jump final during day three of the 2012 U.S. Olympic Track & Field Team Trials at Hayward Field on June 24, 2012, in Eugene, Ore.

Shooter Joshua Richmond poses for a portrait during the 2012 Team USA Media Summit on May 14, 2012, in Dallas.

Jennifer Suhr competes in the women's pole vault final during day three of the 2012 U.S. Olympic Track & Field Team Trials at Hayward Field on June 24, 2012, in Eugene, Ore.