Four in 10 Republicans said they are angry and half say they're dissatisfied with the federal government.
Entrance polls showed Trump doing very well among voters who say they want a president who "tells it like it is", garnering 68 percent of those votes, and among those who want someone who can "bring needed change", picking up 37 percent of those votes. Huckabee won the Iowa caucus in 2008.
The Iowa caucus is the first race of the 2016 presidential campaign for both Republicans and Democrats.
Monday's contest offers the first hard evidence of whether Trump, a reality TV star, can turn the legion of fans drawn to his plainspoken populism into voters. But, given its prime leadoff spot in the primary season, it gets extra attention from presidential campaigns.
Having lost Iowa to Barack Obama eight years ago, she told supporters that she was "breathing a big sigh of relief" after seeing Monday's results. Fat lot of good winning Iowa did Mike Huckabee (more on him in a separate post) and Rick Santorum.
DES MOINES, Iowa (AP) - Ted Cruz, the self-proclaimed outsider and tea party champion, was warmly embraced by conservative Iowa Republicans, whose historic turnout sealed his victory in the Iowa caucuses Monday. While Sanders has a large team in Iowa, his operation got off to a later start, particularly compared with Clinton, who has had staff on the ground in the state for almost a year.
Yet she faced an unexpected challenge from Sanders, the self-declared democratic socialist from Vermont.
And we're leaving tonight and tomorrow afternoon we'll be in New Hampshire.
Cruz backer Shane VanderHart, 43, of Pleasant Hill, Iowa, said he believes Cruz will actually repeal the health insurance program introduced by Obama in 2010, a longtime but pledge by Republican candidates.
Mr Trump said: "We finished second and I want to tell you something, I'm just honoured".
"If I am our nominee, and I will be our nominee thanks to what you have done in this great state, we are going to unify this party and unify the conservative movement, " Rubio said. With the state seemingly tailor-made for his brand of uncompromising conservatism, a loss to Trump will likely be viewed as a failure to meet expectations.
Cruz modeled his campaign after past Iowa Republican winners, visiting all of the state's 99 counties and courting evangelical and conservative leaders. He spent the closing days of the Iowa campaign focused intensely on Rubio, in an unsuccessful attempt to keep the Florida senator from competing for second place.
A Cruz win has upset momentum for Trump, who has led in national polls for the Republican nomination for months. Rubio's stronger-than-expected finish could help cement his status as the favourite of mainstream Republican voters who worry that Cruz and Trump are too caustic to win the November general election. He dismissed the attacks against him as "politics as usual".
Crowds swarmed candidates scurrying throughout Iowa on Sunday, volunteers and campaign organizers knocked on doors and dialed their way through voter contact lists, and a barrage of radio and TV ads - many of them scorchingly negative - provided a harsh soundtrack to an otherwise sunny and unseasonably mild day.
Republicans John Kasich, Chris Christie and Jeb Bush were all spending Monday night in New Hampshire - not only to get a jump on the snow but also on their competitors in a state with voters who are expected to be friendlier to more traditional GOP candidates.
While both parties caucused on the same night in Iowa, they did so with different rules.
Apple estimated to ship 20 million Macs in 2016
But one thing is for sure, Apple is working hard to deliver improvements to its upcoming MacBook Pro 2016. The current configurations use the 2.2- and 2.5- variants, with the 2.8 a luxurious upgrade option.
