Story highlights Bernie Sanders (41%) and Hillary Clinton (40%) are neck-and-neck in Iowa, according to a new survey by Quinnipiac University

Joe Biden, who is mulling a late entry into the race, collected 12% support

Washington (CNN) Bernie Sanders has drawn even with Hillary Clinton for the first time in Iowa, according to a new poll Thursday, underscoring the possibility that the once prohibitive Democratic favorite could lose both of the first two presidential contests.

Sanders edges Clinton 41% to 40% in a new survey by Quinnipiac University , overtaking the former secretary of state as she continues to be dogged by questions about her use of a private email server when she was in public office. Sanders trailed her by 21 points the last time Quinnipiac surveyed the field two months ago, and that margin has more or less held in surveys in Iowa throughout the summer -- until recently.

Vice President Joe Biden, who is mulling a late entry into the race, collected 12% support in Thursday's poll.

For Clinton, the poll will come as a sharp reminder of her 2008 race, when she also faltered in Iowa despite her once-inevitable nominee status. Clinton also trails Sanders in New Hampshire polling, the second nominating state.

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