Washington (CNN) Entrance polling results from the Iowa caucuses show about 45% Democrats are first-time attendees, while about 55% said they had attended before. On the Republican side, about 45% early arrivers say this is their first caucus, a bit more than said so in 2012.

In 2008, 57% of Democrats said they were first-time caucusgoers.

The poll results from shortly after 11 p.m. ET, only reflect the comments of Iowa caucus attendees before they went in to make their decisions Monday night, and each respondent could have easily changed their minds after speaking with pollsters.

"The entrance polls suggest that although we're seeing tight races on both sides, only the Democrats are showing demographic rifts," said Jennifer Agiesta, CNN polling director. "Democratic caucusgoers are divided sharply by age, gender and income. On the Republican side, ideology, religion and on the attributes they value in presidential candidates are the center of the story."

Democratic attendees under the age of 40 tilted heavily to Vermont Sen. Bernie Sanders, including nearly 85% of attendees under the age of 24. But attendees over the age of 50 went more heavily for former Secretary of State Hillary Clinton, and also accounted for almost 60% of all attendees.

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