In the presidential battleground state of Iowa, Clinton is tied with Sen. Rand Paul, R-Ky. (45 percent to 45 percent), and leads New Jersey Gov. Chris Christie by just 1 point (44 percent to 43 percent). She holds larger leads against former Florida Gov. Jeb Bush (46 percent to 42 percent), Sen. Marco Rubio, R-Fla., (49 percent to 40 percent), Sen. Ted. Cruz, R-Texas, (49 percent to 37 percent) and Wisconsin Gov. Scott Walker (50 percent to 37 percent).
The NBC/Marist poll of Iowa was conducted July 7-13 of 558 potential Republican caucus-goers (+/- 4.1% margin of error), 538 potential Democratic caucus-goers (+/- 4.2%) and 1,599 potential general-election voters (+/- 2.5%).
http://www.nbcnews.com/politics/first-read/poll-democrats-ready-hillary-everyone-else-not-much-n157821