DES MOINES, Iowa (CNN) -- Presidential hopeful Mike Huckabee was the big winner in Iowa's GOP caucuses Thursday thanks to big support from two groups of voters: Women and evangelical Christians.
Mike Huckabee appears to have benefited from a strong turnout by evangelical Christian voters.
The latter made up the majority of Republican caucus goers, and CNN's entrance polling showed Huckabee -- a former Baptist pastor -- won 46 percent of that group.
Rival Mitt Romney, who has heavily courted social conservatives, only drew 19 percent of those voters.
"I think the evangelical Christians came out for him; the message was very clear," said CNN contributor William Bennett.
"He is a man of deep conviction and I think people saw that, they couldn't make up their minds about Romney, and decided to stick with [Huckabee]," Bennett said.
Huckabee also overwhelmingly won the female vote, picking up support from about 40 percent of women compared to only 24 percent for Romney.
Republican caucus-goers who told pollsters that a candidate's religious beliefs matter "a great deal" overwhelmingly supported Huckabee by a margin of 56 percent to 11 percent. Watch Huckabee discuss Thursday's caucus »
And Huckabee had considerable support from people who described themselves as "very conservative," with 35 percent of support from that group compared with 23 percent for Romney.
CNN polling of caucus-goers on their way in found illegal immigration was the top issue among Republicans, with 32 percent naming it their biggest concern. Romney had strongly criticized Huckabee on the issue, criticizing his support for in-state tuition benefits for illegal immigrants. Watch GOP caucus-goers express support for their candidates »
Huckabee was known more for his dramatic weight loss than his politics before 2007, and he languished in single digits in the polls for most of the year.
His fortunes started to turn with a surprise second-place showing at the Ames straw poll in August, and social conservatives -- an important GOP voting bloc -- began to move his way in the fall.
He has been vastly outspent by Romney, who poured millions of dollars into a sophisticated get-out-the-vote operation. Nevertheless, he told supporters in Burlington, Iowa, during a last-minute rally that they could send "an important message" Thursday night.
"With the eyes of the world on Iowa, imagine what it's going to be like when they tune into places like Burlington, Waterloo, Des Moines, Dubuque, Sioux City, and they find out that caucus-goers here in Iowa can't be bought, that they can't even be rented, that they'll make up their own minds and they'll make it up for what they stand for," he said.
Huckabee's late surge saw him overtake Romney's longstanding lead in the polls by December. Romney hit back with a wave of advertising critical of Huckabee's record as governor of Arkansas, ads that led the normally affable Huckabee to blast Romney as "dishonest" last weekend. Watch Romney's son react to results »
Thursday night, Huckabee beamed as he claimed an upset win.
"Tonight, we proved that American politics still is in the hands of ordinary folks like you," Huckabee told supporters in Des Moines. Watch Huckabee's victory speech »
"A new day is needed in American politics, just like a new day is needed in American government," he said. "Tonight, it starts here in Iowa, but it doesn't end here. It goes all the way through the other states and ends at 1600 Pennsylvania Avenue." E-mail to a friend
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