Campaign t-shirts

A volunteer at a Bernie Sanders' campaign event wears a shirt decorated with Sanders' image in Fort Dodge, Iowa. REUTERS/Jim Young

A supporter for Donald Trump gestures as he waits before a campaign event in Rock Hill, South Carolina. REUTERS/Chris Keane

Angelo Figueroa of Tracy, California, relaxes before the start of a Donald Trump rally in Reno, Nevada. REUTERS/James Glover II

Supporters of Donald Trump have their picture taken before his campaign rally in Manassas, Virginia. REUTERS/Gary Cameron

Supporter Lindsey English pushes her ear against the door to hear Bernie Sanders speak at a campaign town hall meeting in Hollis, New Hampshire. REUTERS/Brian Snyder

Colby Delaney shows his support on a t-shirt for Donald Trump at the RedState Gathering tailgate party in Atlanta, Georgia. REUTERS/Tami Chappell

Supporters cheer for Bernie Sanders at a rally in Los Angeles. REUTERS/Lucy Nicholson

Supporter Mary McDermott wears a Hillary 2016 t-shirt before a campaign stop by Clinton in Manchester, New Hampshire. REUTERS/Brian Snyder

A supporter holds a Presidential Apprentice t-shirt at a campaign rally with Donald Trump in Worcester, Massachusetts. REUTERS/Brian Snyder

A supporter wears a t-shirt and button as he attends a rally for Donald Trump in Las Vegas, Nevada. REUTERS/Mike Blake

Supporters for Ted Cruz are seen listening to Cruz speak during the conservative leadership project event in Columbia, South Carolina. REUTERS/Chris Keane

Levi Biel places a shirt of Hillary Clinton on a mannequin before actress and screenwriter Lena Dunham speaks at Eight Seven Central screen printers in Des Moines, Iowa. REUTERS/Brian C. Frank

A supporter of Republican presidential candidate Jeb Bush yells "white lives matter" after Bush spoke at a town hall meeting in North Las Vegas, Nevada August 12, 2015. REUTERS/David Becker

Frank McGreevy of Ames, Iowa, listens as Donald Trump speaks during a campaign event at the Surf Ballroom in Clear Lake, Iowa. REUTERS/Scott Morgan

Supporter Carolyn Berndt of Des Moines waits for Donald Trump to speak at a campaign event at Iowa Central Community College in Ft. Dodge. REUTERS/Scott Morgan

Supporters for democratic presidential candidate Bernie Sanders march outside the Wynn Hotel in Las Vegas, Nevada October 13, 2015. Democratic candidates Hillary Clinton, Bernise, Sanders, Martin O'Malley, Jim Webb and Lincoln Chafee will debate...more

Bob Parsons wears a t-shirt in support of Donald Trump while waiting in line to hear Trump speak at the Republican Party Lincoln Day event in Birch Run, Michigan. REUTERS/Rebecca Cook

People listen to Bernie Sanders speak during a special address on Wall Street and financial reform at The Town Hall in New York. REUTERS/Shannon Stapleton

Supporters of Donald Trump hold their hands to their chest as the national anthem is played at a campaign rally in Concord, New Hampshire. REUTERS/Gretchen Ertl