Republican presidential candidate Carly Fiorina speaks at a rally on the campus of Georgia Tech in Atlanta on Dec. 8. (John Bazemore/AP)

The campaign of Carly Fiorina, a business executive and the only female candidate in the Republican primary race, is foundering.

Fiorina gained a key opportunity this fall when she rose in the polls after two strong debate performances that showcased her direct delivery style and command of the issues. But with businessman Donald Trump monopolizing media attention, and without the deep campaign organization of the other leading candidates, Fiorina is seeing her opportunity slip away.

Her road back to relevance could prove challenging, with voting in Iowa and New Hampshire just weeks away. The effort begins Tuesday in Nevada, where CNN will host the final Republican debate of the year.

“She sort of had a moment, then she faded,” said Katie Packer Gage, former deputy campaign manager for Mitt Romney. “If she’s going to stay in this, she has to find her second act.”

A particular challenge for Fiorina, who has rooted her candidacy in economic issues and her business experience, is her mixed record at the helm of Silicon Valley giant Hewlett-Packard. She has also struggled to reach voters focused more on national security after the terrorist attacks in Paris and San Bernardino, Calif.

The GOP presidential candidates face off Tuesday for the last time this year. Here's what you should watch for at the prime-time CNN debate. (Sarah Parnass/The Washington Post)

Fiorina touts her credentials as an adviser to the Defense Department and the State Department, and she invariably addresses the Israeli prime minister as “my good friend Bibi Netanyahu.” But most voters see her primarily as a businesswoman.

Meanwhile, riding on the strength of his experience as a federal prosecutor in the wake of the Sept. 11, 2001, attacks, New Jersey Gov. Chris Christie’s stock has risen dramatically in New Hampshire since Paris.

“It’s harder for her because she’s not naturally considered an expert on national security,” GOP pollster Frank Luntz said. “National security has become the number one issue for Republicans, and it’s not even close. And when you move from economic security to national security, that’s not good for her.”

Fiorina’s peak followed two standout debate performances that brought first and second looks from pundits and voters alike. In the undercard round of the first GOP debate of the season, in August in Cleveland, Fiorina won enough accolades and support to propel her onto the main stage for September’s CNN-sponsored debate at the Reagan Presidential Library in California.

There, she went toe to toe with Trump, who had made disparaging comments about her appearance. And she got the attention of social conservatives, particularly women, by coming out hard against Planned Parenthood and abortion.

At her peak, in early October, polls showed Fiorina in second place in New Hampshire, according to an average of polls compiled by Real Clear Politics. In Iowa and South Carolina, she placed third. But those gains have since disappeared, most notably in Iowa and South Carolina, where she now hovers at 3 percent or less.

In New Hampshire, where the number of Fiorina visits rivals that of Christie and Sen. Lindsey O. Graham (R-S.C.), her predicament is only marginally less dire. Recently, however, she conceded that while she might not win in the state, her candidacy hinges on her ability to overperform there and elsewhere.

Republican presidential candidate Carly Fiorina took on Trump and his comment regarding her "persona." Hear her other memorable moments from the second GOP debate. (CNN)

“I need to exceed expectations in New Hampshire,” she told TV station WMUR in Manchester. “I need to exceed expectations in Iowa, and I need to keep going because this is a long race.”

Fiorina has spent most of her time in those three early-voting states.

Her campaign also relies heavily on an independent super PAC called CARLY for America for traditional campaign activities.

The organization is prohibited by law from strategizing privately with the campaign but may do so publicly. Fiorina’s events, for example, are announced by her campaign in advance. CARLY for America then springs into action to put supporters and other voters in the audience.

At the events, super PAC volunteers hand out CARLY for America stickers and pins, collect voter information at a front desk as people enter, and even provide the backdrop for the candidate as she speaks. Fiorina’s super PAC also bears most of the burden of canvassing and ground organizing. It has taken the lead in recruiting some endorsers, hired paid staff members in a dozen states and paid for air time in New Hampshire for a biographical movie about Fiorina.

If the performance of Fiorina’s campaign is a test of the efficacy of that arrangement, however, the results have been lukewarm. One reason may be the way the arrangement has segregated the candidate from the grass-roots elements of her campaign, making it more difficult for her to build on the buzz generated by the debates in a focused and nimble way.

The campaign and the super PAC were slow to reinforce Fiorina’s debate messages with ads that might have boosted her name recognition among Republicans at a time when interest in her was spiking.

It wasn’t until early December, more than two months after the second debate — and after Fiorina’s poll numbers fell back to the low single digits — that the super PAC unveiled its first campaign ad buy in New Hampshire. The PAC announced a roughly $1 million radio and television campaign that dubbed Fiorina “a conservative outsider.” And CARLY for America’s executive director, Steve DeMaura, called on supporters to make 25 calls on her behalf.

“If I had seen how she performed in that first debate, then I would have had a whole plan building on that, and looked at a whole media strategy and events strategy that would have played on that one performance,” said Packer Gage, the Romney adviser. “Because they have a whole outside team doing that, it’s difficult to do that. It’s the left and right hands not talking.”

Fiorina’s message and biography have also contributed to her struggle to gain traction as an “outsider” candidate. Part of the difficulty is competing with the relentless, dominating bombast of Trump.

“As an anti-establishment candidate, you’ve got to do some things that are anti-establishment,” said Chip Felkel, a veteran Republican strategist in South Carolina. “Unfortunately for Fiorina, she doesn’t seem to be controversial or loud enough to get traction with the anti-establishment camp.”

In addition, the cornerstone of Fiorina’s candidacy — her tenure as chief executive of Hewlett-Packard — is also a liability.

On the campaign trail, Fiorina describes her leadership of the technology giant in glowing terms: She saved the company from folding during the dot-com bust. She has also argued that being fired by the company’s board proved her mettle.

But Fiorina also oversaw thousands of layoffs and was in charge during a period when HP’s stock prices tumbled — allowing opponents and voters to question her business acumen and fitness for the White House.

Voters say her experience at HP doesn’t necessarily disqualify her as a candidate, but it has raised questions.

“Just based on when she came to Hewlett-Packard, and she had to let go of all those people and downsize the company because it was in disrepair or whatever. Those are the things that you hear,” said Ray Andjeski, 59, a Republican voter who owns a pest-control company in Ohio.

But, he added, “when a company is in disrepair, tough decisions have to be made.”

Fiorina has also attracted negative attention for statements that proved to be untrue. She came under fire after the Reagan Library debate for describing a video she saw of an aborted fetus lying on a table and kicking as doctors discussed harvesting its organs for fetal tissue research. No such video has surfaced.

Fiorina’s advisers say they see the primary race as a marathon rather than a sprint. They are running a lean operation, unlike other campaigns that have burned through cash with little polling gain to show for it — or that have run out of money to continue.

Voters say almost universally that they are impressed by the candidate herself: her policy knowledge, her direct delivery, and her varied career in the private sector and in public life.

But many seem unwilling to commit to her — they’re open to the idea of supporting her but discouraged by her continuing struggle to gain broad support.

“If she can pull ahead in the nomination process in the primary, I’d love to vote for her,” South Carolina voter Donna Starkey, 71, said this week.

Starkey first saw Fiorina during a campaign swing in October. While she is intrigued, she isn’t sold.

A key test would be “being able to stand out and pull ahead in a difficult race with so many candidates,” Starkey noted.

Andjeski, the Ohio voter, said he once considered Fiorina one of his top candidates after hearing her speak at a leadership conference before she ran for president. But he said he is now leaning toward Sen. Marco Rubio (R-Fla.).

“My only concern is that she didn’t do better in the polls,” Andjeski said. “I would vote for her over Rubio if she were doing better.”