Republican presidential candidate Donald Trump waves to the crowd at his "Make America's Military Great Again" rally, which was held aboard the retired USS Iowa battleship, in Los Angeles, Calif., on Sept. 15, 2015.
Photo by Mark Peterson/Redux for MSNBC

Poll: Trump hits highest mark yet, but Carson is close behind

Updated

Real estate mogul Donald Trump remains the front-runner in the Republican presidential field, while former neurosurgeon Ben Carson holds a close second place, a new NBC News/Wall Street Journal poll shows.

With the backing of 25 percent of Republican primary voters, Trump is at his highest level of support in the poll since entering the 2016 race. Carson now gets the support of 22 percent of Republican voters, remaining within the margin of error of his first-place rival. Last month, 21 percent of GOP primary voters said Trump was their first choice for the party’s nomination, while 20 percent picked Carson.

Sen. Marco Rubio of Florida is in third place, getting support from 13 percent of GOP voters, while Sen. Ted Cruz of Texas (at 9 percent, up four points since last month ) and Jeb Bush (at 8 percent, up one point since last month) are in fourth and fifth place, respectively.

The new poll, which surveyed respondents from Oct. 15 to Sunday, saw a slight dip in support for former Hewlett-Packard executive Carly Fiorina, who fell from 11 percent last month to 7 percent this month. Fiorina won a boost late this summer from strong performances in the two televised Republican debates.

Receiving support in the low single digits in the poll are former Arkansas Gov. Mike Huckabee (3 percent), Ohio Gov. John Kasich (3 percent), Sen. Rand Paul of Kentucky (2 percent) and New Jersey Gov. Chris Christie (1 percent).

Five candidates still in the race — Sen. Lindsey Graham of South Carolina, former Sen. Rick Santorum of Pennsylvania, former New York Gov. George Pataki, Louisiana Gov. Bobby Jindal and former Virginia Gov. Jim Gilmore — registered less than 1 percent support.

Carson’s upside potential

While Trump leads when GOP primary voters are asked about their first choice for the party’s nomination, Carson boasts the highest share of voters who say they can see themselves supporting him. Seventy-four percent said that they can imagine backing Carson for the GOP nod, while just 20 percent said they could not.

But Trump has also gained ground when it comes to whether or not potential voters can picture themselves backing him. Fifty-nine percent of GOP voters now say they can see themselves supporting Trump, while 36 percent disagree. Just last month, a slight majority — 52 percent — said they could not see themselves backing the real estate mogul, while 47 could envision it.

Rubio (65 percent could support/26 percent could not support) and Fiorina (56 could support/30 percent could not support) also show significant possible upsides among GOP voters.

The gap is narrower for Bush (51 percent could support/44 percent could not support) and Cruz (48 percent could support/41 percent could not support.)

When asked which candidate would be their second choice, GOP respondents tended to choose Carson, followed by Trump and Rubio. That tally means that, when GOP primary voters’ first and second choices are combined, the former neurosurgeon manages to best Trump, 44 percent to 39 percent.

Carson runs strongest among very conservative Republicans, with 28 percent of that group’s support, while Trump leads among those who say they are moderate or liberal (31 percent). Trump also leads among GOP primary voters who listen to talk radio (33 percent to Carson’s 22 percent) and those who describe themselves as Tea Party supporters (28 percent to Carson’s 22 percent).

The NBC News/ Wall Street Journal poll was conducted Oct. 15 to 18. The margin of error for 400 Republican primary voters is +/- 4.9 percent.

This story originally appeared on NBCNews.com

Ben Carson, Carly Fiorina, Donald Trump and Polling

Poll: Trump hits highest mark yet, but Carson is close behind

Updated