Story highlights The former Secretary of State has 44% while the Vermont senator has 42%. And 11% of voters are undecided, unchanged from February 5

At 39%, the Republican front-runner is leading Florida Sen. Marco Rubio by 20 points

Washington (CNN) While Donald Trump continues his dominance over his Republican rivals, Hillary Clinton has a very narrow margin over Bernie Sanders, in a Quinnipiac national poll released Wednesday.

The former secretary of state has 44% of voters' support while the Vermont senator has 42%. And 11% of voters are undecided, unchanged from a February 5 national survey from Quinnipiac. Clinton was ahead of Sanders by two percentage points in the February 5 survey as well.

"Sen. Bernie Sanders and Secretary Hillary Clinton are neck and neck. But while Bernie has the trust, Hillary has the experience. Two different measurements of two dissimilar candidates," said Tim Malloy, assistant director of the Quinnipiac University Poll.

Other national polls haven't shown the Democratic race so close, though Quinnipiac is one of the few major polling outlet to release national results since voting began this month.

The Democratic gender gap is shrinking. Female participants in the survey back Clinton over Sanders 47% to 41%, while men supported Sanders 44% to 40%.

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