This is Quinnipiac's first Iowa poll ever:
Do you approve or disapprove of the way Barack Obama is handling his job as President?45-50 disapprove
If the election for President were being held today, and the candidates were Hillary Clinton the Democrat and Marco Rubio the Republican, for whom would you vote? 48-37 Clinton
If the election for President were being held today, and the candidates were Hillary Clinton the Democrat and Rand Paul the Republican, for whom would you vote? 46-42 Clinton
If the election for President were being held today, and the candidates were Joe Biden the Democrat and Marco Rubio the Republican, for whom would you vote? 40-39 Rubio
If the election for President were being held today, and the candidates were Joe Biden the Democrat and Rand Paul the Republican, for whom would you vote?44-39 Paul
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From May 15 - 21, Quinnipiac University surveyed 1,411 registered voters with a margin of error of +/- 2.6 percentage points. Live interviewers call land lines and cell phones.
http://www.quinnipiac.edu/institutes-and-centers/polling-institute/iowa/release-detail?ReleaseID=1898