 "U.S. Republican presidential candidate Ted Cruz speaks at a campaign event at the Adventure Christian Community in Davenport, Iowa. Photo: Reuters")
US Senator Ted Cruz beat billionaire Donald Trump in Iowa's Republican presidential nominating contest on Monday, dealing a big upset to the national front-runner in the race to be their party's White House nominee in 2016.
Cruz, a conservative lawmaker from Texas, won with 28% of the vote compared to 24% for businessman Trump, according to MSNBC.
Marco Rubio, a US senator from Florida, came in third place with 23%, making him easily the leader among establishment Republican candidates.
Former Secretary of State Hillary Clinton held a slim lead in the Democratic race over rival Bernie Sanders, a self-described democratic socialist US senator from Vermont.
Former Maryland Governor Martin O'Malley, who had trouble gaining any traction in the Democratic race, planned to suspend his campaign at 9:30 p.m. CST (0330 GMT), according to a Democrat with knowledge of his plans.
On the Republican side, former Arkansas Governor Mike Huckabee said he was suspending his campaign for the Republican party nomination. Huckabee won the Iowa caucus in 2008.
