WASHINGTON — (CNN) The first CNN/ORC poll of likely Democratic caucus-goers in Iowa finds Hillary Clinton firmly in the lead in the state that kicks off the nation’s nominating contests, holding a 50% to 31% lead over upstart Vermont Senator Bernie Sanders. Vice President Joe Biden, who has yet to decide whether to make a run for presidency, lands in third place with 12%, with the rest of the field at 1% or less.

The slightly-tighter-than-national race reflects two broad divides among Iowa’s Democratic voters: a gender gap and an ideological split. Among women, Clinton tops Sanders by more than 30 points, 58% to 26%. Among men, the two are even: 38% back Clinton, 37% Sanders. Likewise, among the party’s moderates, 57% back Clinton, 21% Sanders, while liberals split 46% for Clinton to 41% for Sanders. And liberals are most apt to say they are firm in their choice: Fully 42% say they’ve definitely decided whom to support, compared with 30% overall.

All told, nearly half of Iowa’s likely Democratic caucus-goers say they’ve either made up their minds about the race or are leaning toward a candidate (46%), and among that group, Clinton stands at 53%. Sanders jumps to 41% among those who have made up their minds and despite not having made up his own mind about running, Biden has 5%. Former Maryland governor Martin O’Malley rounds out the list at 1%.

Should Biden decide not to run, the poll suggests Clinton would get a bigger boost than Sanders. Reallocating Biden’s supporters to their second choice candidate, 58% would back Clinton, 32% Sanders, 2% former O’Malley, 1% former Virginia senator Jim Webb and less than 1% would back former Rhode Island governor Lincoln Chafee.

Sanders’ economic message resonates

Sanders’ unexpected rise to second place in the race for the Democratic nomination relies heavily on a message that focuses on economic populism, and on two matters central to that message – how to handle the economy and understanding of average Americans’ problems – the poll suggests Sanders has made some headway. While Clinton has a commanding lead as the candidate better trusted to handle foreign policy (66% trust her, 18% Vice President Joe Biden, 9% Sanders), and health care (54% say Clinton would do the best job, 28% Sanders, 13% Biden), on the economy, the gap between Clinton and Sanders is far narrower, with less than half saying they trust Clinton (42% vs. 31% who favor Sanders). It gets even tighter among those who say the economy is their top issue. That group splits 41% for Clinton to 38% for Sanders on which candidate they trust most to handle their top concern.

And Iowa Democrats overall are split on whether Clinton or Sanders best understands the problems facing people like you, 40% say Clinton does, 39% Sanders. On that, the poll finds a sharp divide by education alongside an ideological split. Those with a college degree are more likely to see Sanders as the most empathetic candidate, 46% Sanders to 29% Clinton, while those without college degrees think Clinton is more empathetic, 46% Clinton to 35% Sanders. And liberals are more likely to see Sanders as tops here, 51% to 37% for Clinton, while moderates break Clinton’s way, 40% to 29%.

Overall, Clinton has a slightly larger edge as the candidate who best represents the values of Democrats like yourself, 41% to 33%.

Honesty as a factor

Sanders outpaces Clinton on just one measure in the poll, honesty. He tops the list when caucus-goers are asked which Democratic candidate is the most honest and trustworthy, 35%, while 28% say Clinton is. The two are also close on energy policy, with 37% saying they think Clinton would do the better job, 31% Sanders.

Asked to name the top issues they’ll consider in choosing a presidential candidate to support next year, Iowa’s likely Democratic caucusgoers are broadly focused on the economy, with 31% naming an economy-related issue, 16% cite health care, 9% education, and 8% foreign policy.

The poll was conducted August 7-11 among a statewide sample of 2,014 Iowa adults, 429 of whom were identified as likely Democratic caucus-goers based on questions about whether they are registered to vote, likelihood of voting, past voting behavior and interest in the campaign. The margin of sampling error for results among the sample of likely Democratic caucus attendees is plus or minus 4.5 percentage points. Full Results

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