About half of likely Democratic caucus-goers -- 51% -- said they support Clinton, compared to 42% for Sanders and just 4% for former Maryland Gov. Martin O'Malley, according to the Quinnipiac University poll released Wednesday.
The results mark very little change from a similar survey released October 23.
Most of those surveyed said they believe Clinton (85%) has a better shot than Sanders (54%) at defeating a Republican candidate, said Peter Brown, assistant director of the Quinnipiac University Poll, in a statement accompanying the poll results.
About 47% of the Democrats polled said Sanders would best handle the economy, while 42% said they believed Clinton would.
Topping the list of issues respondents said they cared about most were the economy and jobs (36%), followed by climate change (15%), foreign policy (12%) and health care (11%).
"It's not that Iowa Democrats are in love with Secretary Clinton right now. They even think Sanders would be better handling the economy, generally the hallmark of the candidate who wins the Democratic nomination," Brown said. "But despite all the things about Clinton that gives Democrats pause, there is one thing that unites them: She looks like a winner in November."
Clinton's favorability rating was 81%, with 68% of participants saying they believe she is honest and trustworthy.
While 89% of participants said Sanders is honest and trustworthy -- more than 30 percentage points higher than Clinton, -- only 66% believe he has the right kind of experience to be president. But nearly all respondents -- 95% -- said Clinton has the right kind of experience to be president.
"The only way Secretary Clinton is going to lose the nomination is a scenario in which she drops the early Iowa and New Hampshire contests to Sen. Sanders, who then might become the 'momentum' candidate," Brown said.
The poll surveyed 543 likely Iowa Democratic caucus participants from November 16-22 and has a margin of error of plus or minus 4.2 percentage points.