After eking their way into the first Republican presidential debate last month, Gov. Doug Burgum of North Dakota and former Arkansas Gov. Asa Hutchinson, long-shot candidates, appear to be in jeopardy of failing to qualify for the party’s second debate next week.
Both have been registering support in the low single digits in national polls and in the polls from early nominating states that the Republican National Committee uses to determine eligibility.
The threshold is higher for this debate, happening on Wednesday at the Ronald Reagan Presidential Library in Simi Valley, Calif. Several better-known G.O.P. rivals are expected to make the cut — but the candidate who is perhaps best known, former President Donald J. Trump, is again planning to skip the debate.
Some of Mr. Trump’s harshest critics in the G.O.P. have stepped up calls for the party’s bottom-tier candidates to leave the crowded race, consolidating support for a more viable alternative to the former president.
Lance Trover, a spokesman for the Burgum campaign, contended in an email on Wednesday that Mr. Burgum was still positioned to qualify for the debate. Mr. Hutchinson’s campaign did not immediately respond to requests for comment.
Emma Vaughn, a spokeswoman for the R.N.C., said in an email on Wednesday that candidates have until 48 hours before the debate to qualify. She declined to comment further about which ones had already done so.
Before the first debate on Aug. 23, the R.N.C. announced it was raising its polling and fund-raising thresholds to qualify for the second debate, which will be televised by Fox Business. Candidates must now register at least 3 percent support in a minimum of two national polls accepted by the R.N.C. The threshold for the first debate was 1 percent.
Debate organizers will also recognize a combination of one national poll and polls from at least two of the following early nominating states: Iowa, New Hampshire, Nevada and South Carolina.
“While debate stages are nice, we know there is no such thing as a national primary,” Mr. Trover said in a statement, adding, “Voters in Iowa and New Hampshire are the real people that narrow the field.”
Mr. Burgum’s campaign has a plan to give him a boost just before the debate, Mr. Trover added, targeting certain Republicans and conservative-leaning independents through video text messages. A super PAC supporting Gov. Ron DeSantis of Florida, who is running a distant second to Mr. Trump in Republican polls, has used a similar text messaging strategy.
Mr. Burgum, a former software executive, is also harnessing his wealth to introduce himself to Republicans through television — and at considerable expense. Since the first debate, a super PAC aligned with him has booked about $8 million in national broadcast, live sports and radio advertising, including a $2 million infusion last week, according to Mr. Burgum’s campaign, which is a separate entity. His TV ads appeared during Monday Night Football on ESPN.
As of Wednesday, there were six Republicans who appeared to be meeting the national polling requirement, according to FiveThirtyEight, a polling aggregation site.
That list was led by Mr. Trump, who is ahead of Mr. DeSantis by an average of more than 40 percentage points. The list also includes the multimillionaire entrepreneur Vivek Ramaswamy; Nikki Haley, the former South Carolina governor and Mr. Trump’s United Nations ambassador; former Vice President Mike Pence; and former Gov. Chris Christie of New Jersey.
And while Senator Tim Scott of South Carolina was averaging only 2.4 percent support nationally as of Wednesday, he is also expected to make the debate stage by relying on a combination of national and early nominating state polls to qualify.
Mr. Scott has performed better in places like Iowa and his home state than in national polls, and his campaign has pressed the R.N.C. to place more emphasis on early nominating states.
The R.N.C. also lifted its fund-raising benchmarks for the second debate. Only candidates who have received financial support from 50,000 donors will make the debate stage — 10,000 more than they needed for the first debate. They must also have at least 200 donors in 20 or more states or territories.
While Mr. Burgum’s campaign said that it had reached the fund-raising threshold, it was not immediately clear whether Mr. Hutchinson had.
Both candidates resorted to some unusual tactics to qualify for the first debate.
Mr. Burgum offered $20 gift cards to anyone who gave at least $1 to his campaign, while Politico reported that Mr. Hutchinson had paid college students for each person they could persuade to contribute to his campaign.
Candidates will still be required to sign a loyalty pledge promising to support the eventual Republican nominee, something that Mr. Trump refused to do before skipping the first debate.
Shane Goldmacher contributed reporting.