NBC Poll: Trump Dominates, Jeb Fades to 3rd in Iowa, 4th in NH

A new NBC News/Marist Poll shows Donald Trump is leading in Iowa and New Hampshire, with former Florida Gov. Jeb Bush fading while retired neurosurgeon Ben Carson and Ohio Gov. John Kasich's numbers are climbing.

In Iowa, Trump is leading with 29 percent of the 390 potential Republican caucus-goers polled, with Carson following at 22 percent. They were the only two candidates to receive double digit results.

Also in the Iowa poll, which carried a margin of error of plus or minus five points:

• Bush is in third with 6 percent;
• Former Hewlett-Packard CEO Carly Fiorina, Kentucky Sen. Rand Paul and Wisconsin Gov. Scott Walker each received 5 percent;
• Texas Sen. Ted Cruz, Florida Sen. Marco Rubio, and Louisiana Gov. Bobby Jindal received 4 percent.
• Former Arkansas Gov. Mike Huckabee, 3 percent;
• New Jersey Gov. Chris Christie and Kasich, 2 percent each;
• Former Pennsylvania Sen. Rick Santorum 1 percent;
• Former New York Gov. George Pataki, former Texas Gov. Rick Perry, former Virginia Gov. Jim Gilmore, and South Carolina Sen. Lindsey Graham, all less than 1 percent.

In New Hampshire, Trump has a larger lead, receiving 28 percent of the 413 potential Republican primary voters, putting him far ahead of his nearest challenger, Kasich, at 12 percent. Carson came in at third, with 11 percent. This poll carried a margin of error of plus or minus 4.8 percentage points.

In other New Hampshire rankings:

• Bush is at 8 percent;
• Fiorina received 6 percent;
• Walker received 4 percent;
• Paul, Cruz, and Christie, 5 percent;
• Rubio, 3 percent;
• Huckabee, 2 percent;
• Graham and Jindal, 1 percent;
• Santorum, Perry, Pataki, and Gilmore, all less than 1 percent.

Walker led the Iowa poll in July at 18 percent, with Trump in second at 17 percent and Bush third, with 12 percent. Meanwhile, Trump led in New Hampshire in July with 21 percent followed by Bush, at 14 percent, and Walker at 12 percent.