Wisconsin Gov. Scott Walker speaks during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Walker
Wisconsin Gov. Scott Walker speaks during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Cruz
Sen. Ted Cruz, R-Texas, speaks during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Walker
Wisconsin Gov. Scott Walker waves as he walks off stage after speaking at the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Walker
Wisconsin Gov. Scott Walker is interviewed by host Bruce Rastetter, right, during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Bush
In this March 7, 2015, photo, former Florida Gov. Jeb Bush is interviewed by host Bruce Rastetter, left, during the Iowa Agriculture Summit in Des Moines, Iowa. After a flurry of fundraising, formal speeches about economics and global affairs Bush got down to business this weekend appearing at the Pizza Ranch in Cedar Rapids, Iowa, after a stop at the Agricultural Summit. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
Presidential Summit Agriculture
Sen. Ted Cruz, R-Texas, is interviewed by host Bruce Rastetter, right, during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Perry
Former Texas Gov. Rick Perry speaks during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Pataki
Former New York Gov. George Pataki speaks during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Santorum
Former Penn. Sen. Rick Santorum is interviewed by host Bruce Rastetter, right, during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Perry
Former Texas Gov. Rick Perry waves as he walks on stage during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
Image Credit: ASSOCIATED PRESS
GOP 2016 Iowa Chrisite
New Jersey Gov. Chris Christie speaks during the Iowa Agriculture Summit, Saturday, March 7, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)
