CNBC rules will limit Oct. 28 GOP main debate to nine candidates
Republican presidential candidates including (L-R), former U.S. Senator Rick Santorum, former New York Governor George Pataki, U.S. Senator Rand Paul, former Arkansas Governor Mike Huckabee, U.S. Senator Marco Rubio, U.S. Senator Ted Cruz, Dr. Ben Carson, businessman Donald Trump, former Florida Governor Jeb Bush, Wisconsin Governor Scott Walker, former CEO Carly Fiorina, Ohio Governor John Kasich and New Jersey Governor Chris Christie pose before the start of the second official Republican presidential candidates debate of the 2016 U.S. presidential campaign at the Ronald Reagan Presidential Library in Simi Valley, California, on Sept. 16, 2015. Photo by Mario Anzuoni for Reuters.

U.S. Republican presidential candidates polling an average of at least 2.5 percent in designated national opinion polls will qualify for a prime-time debate in Colorado on Oct. 28, the debate's host, CNBC, said on Wednesday.

Candidates below that level, but scoring at least 1 percent in any of the six designated polls, will earn a place in the second-tier debate immediately preceding the main event, the cable news network said.

The two-hour prime-time debate, the third for the crowded Republican field, will start at 8 p.m. EDT at the University of Colorado Boulder and focus on topics including the economy, taxes and jobs, CNBC said.

While 3 percent was set as the official threshold for the main debate, the network said the average of the polls conducted between Sept. 17 and Oct. 21 would be rounded up to that figure for any candidate with at least 2.5 percent.

Nine candidates would currently qualify for the main debate, according to a Real Clear Politics average of polls. That group would consist of front-runner Donald Trump, retired physician Ben Carson, former businesswoman Carly Fiorina, Florida Senator Marco Rubio, former Florida Governor Jeb Bush, Texas Senator Ted Cruz, Ohio Governor John Kasich, former Arkansas Governor Mike Huckabee and New Jersey Governor Chris Christie.

Candidates currently qualifying for the second-tier debate would be Kentucky Senator Rand Paul, Louisiana Governor Bobby Jindal, former Pennsylvania Senator Rick Santorum and former New York Governor George Pataki.

The main CNN Republican debate on Sept. 16 featured 11 candidates, including Fiorina, who did not qualify for the first prime-time debate on Fox News on Aug. 6 that involved 10 candidates.

For more on the 2016 presidential race, see the Reuters blog, “Tales from the Trail.”

(Reporting by Peter Cooney; Editing by Sandra Maler and Eric Beech)