IA - 2016 Democratic Presidential Primary: Hillary Clinton 65% - Bernie Sanders 24% - Martin O'Malley 5% - (Monmouth Univ. 10/27/2015) chart & more info

Bernie Sanders
Hillary Clinton
  • Clinton +41

IA - 2016 GOP Presidential Primary: Ben Carson 32% - Donald Trump 18% - Marco Rubio 10% - (Monmouth Univ. 10/26/2015) chart & more info

Donald Trump
Ben Carson
  • Carson +14

IA - 2016 GOP Presidential Primary: Ben Carson 31% - Donald Trump 19% - Marco Rubio 10% - (Loras College 10/26/2015) chart & more info

Donald Trump
Ben Carson
  • Carson +12

IA - 2016 GOP Presidential Primary: Ben Carson 28% - Donald Trump 19% - Marco Rubio 9% - (Des Moines Register/Bloomberg 10/23/2015) chart & more info

Donald Trump
Ben Carson
  • Carson +9

IA - 2016 Democratic Presidential Primary: Hillary Clinton 51% - Bernie Sanders 40% - Martin O'Malley 4% - (Quinnipiac 10/23/2015) chart & more info

Bernie Sanders
Hillary Clinton
  • Clinton +11

IA - 2016 GOP Presidential Primary: Ben Carson 28% - Donald Trump 20% - Marco Rubio 13% - (Quinnipiac 10/22/2015) chart & more info

Donald Trump
Ben Carson
  • Carson +8

IA - 2016 Democratic Presidential Primary: Hillary Clinton 48% - Bernie Sanders 41% - Martin O'Malley 2% - (Des Moines Register/Bloomberg 10/22/2015) chart & more info

Bernie Sanders
Hillary Clinton
  • Clinton +7

IA - 2016 Presidential Election: Bernie Sanders 48% - Donald Trump 43% - (NBC/WSJ/Marist 10/06/2015) chart & more info

Donald Trump
Bernie Sanders
  • Sanders +5

IA - 2016 Presidential Election: Jeb Bush 46% - Bernie Sanders 44% - (NBC/WSJ/Marist 10/06/2015) chart & more info

Bernie Sanders
Jeb Bush
  • Bush +2

IA - 2016 Presidential Election: Carly Fiorina 45% - Bernie Sanders 42% - (NBC/WSJ/Marist 10/06/2015) chart & more info

Bernie Sanders
Carly Fiorina
  • Fiorina +3

IA - 2016 Presidential Election: Carly Fiorina 52% - Hillary Clinton 38% - (NBC/WSJ/Marist 10/06/2015) chart & more info

Hillary Clinton
Carly Fiorina
  • Fiorina +14

IA - 2016 Presidential Election: Jeb Bush 50% - Hillary Clinton 40% - (NBC/WSJ/Marist 10/06/2015) chart & more info

Hillary Clinton
Jeb Bush
  • Bush +10

IA - 2016 Presidential Election: Donald Trump 48% - Hillary Clinton 41% - (NBC/WSJ/Marist 10/06/2015) chart & more info

Hillary Clinton
Donald Trump
  • Trump +7

IA - 2016 Democratic Presidential Primary: Hillary Clinton 33% - Bernie Sanders 28% - Joe Biden 22% - (NBC/WSJ/Marist 10/04/2015) chart & more info

Bernie Sanders
Hillary Clinton
  • Clinton +5

IA - 2016 GOP Presidential Primary: Donald Trump 24% - Ben Carson 19% - Carly Fiorina 8% - (NBC/WSJ/Marist 10/04/2015) chart & more info

Ben Carson
Donald Trump
  • Trump +5

...
11
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