Online poll: Sanders up by 1 point in Iowa
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A week before the Iowa caucuses, Bernie SandersBernard (Bernie) SandersChris Murphy’s profile rises with gun tragedies Clip shows Larry David and Bernie Sanders reacting after discovering they're related For now, Trump dossier creates more questions than answers MORE has a slim lead over Hillary ClintonHillary Diane Rodham ClintonChris Murphy’s profile rises with gun tragedies DNC, RNC step up cyber protections Gun proposal picks up GOP support MORE in the race for the Democratic Presidential nomination, according to a new online poll.

The CBS News “Battleground Tracker” poll released Sunday morning shows Sanders with a 1-point lead over Clinton, 47 to 46 percent.

Martin O’Malley has 5 percent.

Sanders maintains his wide lead in New Hampshire, 57 to 38 percent, according to the poll, while Clinton still commands a strong advantage, 60 to 38 percent, in South Carolina.

YouGov conducted the poll for CBS News. It has an 8.9 percent margin of error in Iowa, an 8.2 percent margin of error in New Hampshire and a 9.4 percent margin of error in South Carolina.