With less than three weeks until ballots are cast in the Iowa caucuses, Democratic presidential rivals Hillary ClintonHillary Rodham ClintonShaky Democratic platform will collapse without oil, gas Hillary, go walk the streets; it will humanize you. Lose the bubble. Trump floats opposition to debate schedule MORE and Bernie SandersBernie SandersTrump floats opposition to debate schedule 100 days to go in volatile race What does Bill think of Hillary's Chris Wallace interview? MORE are neck and neck in the Hawkeye State.
This is the closest Sanders has come to overtaking Clinton in Iowa.
The tightening race — and Sanders’s slim lead in New Hampshire — has been accompanied by more antagonistic campaign rhetoric.
Clinton has gone after the Vermont senator for his votes on gun-related bills, calling him a “reliable vote for the gun lobby.”
Sanders fired back, saying Clinton’s attack was “mean-spirited” and “unfair” and pointing to his D-minus rating with the National Rifle Association.
He also said Clinton’s more aggressive tone is a sign that her campaign is in “serious trouble.”
Martin O’Malley places a distant third in the new poll, with 4 percent support. Fourteen percent of respondents said they are still uncommitted or not sure whom they will support.
The poll of 503 likely Democratic caucusgoers, conducted Jan. 7–10, has a margin of error of 4.4 percentage points.