Iowa caucuses get under way – in pictures

Ron Paul waits in the corridor before appearing at a campaign stop in Mason City with his son Rand Photograph: T.J. Kirkpatrick/Corbis

Rick Perry at the Hotel Pattee in the aptly-named town of Perry, Iowa Photograph: Charlie Neibergall/AP

Minnesota congresswoman Michele Bachmann waves from her battle bus at Valley high school in West Des Moines Photograph: Eric Gay/AP

Mitt Romney speaks at a campaign rally in Des Moines Photograph: Jewel Samad/AFP/Getty Images

Rick Santorum wrestles with a media scrum in Des Moines Photograph: Rick Wilking/Reuters

Former House speaker Newt Gingrich takes questions from voters at Elly's Tea and Coffee in Muscatine Photograph: Jeff Haynes/Reuters

Volunteers for the Rick Santorum and Rick Perry campaigns ready to hand out the official merchandise in Ankney Photograph: Joshua Lott/Reuters

Caucusgoers arrive to vote at the University of Northern Iowa in Cedar Falls Photograph: Jeff Haynes/Reuters

Voters arrive for their caucus in Des Moines Photograph: Jewel Samad/AFP/Getty Images

Newt Gingrich with his wife Callista in Muscatine Photograph: Charles Dharapak/AP

Michele Bachmann, accompanied by her mother Jean, speaks to the caucus at the University of Northern Iowa in Cedar Falls Photograph: Jeff Haynes/Reuters

A Rick Perry supporter leaves a caucus training session at the Sheraton hotel in West Des Moines Photograph: Jonathan Gibby/Getty Images

The University of Northern Iowa in Cedar Falls Photograph: Jeff Haynes/Reuters

An Iowa state flag at a campaign rally in Clive for former Massachusetts governor Mitt Romney Photograph: Brian Snyder/Reuters

Ron Paul followers show their support at a campaign stop in West Des Moines Photograph: Jim Young/Reuters