Former U.S. President Donald Trump speaks during the Conservative Political Action Conference (CPAC) at National Harbor in Maryland, the United States, Feb. 24, 2024. (Photo by Aaron Schwartz/Xinhua)

As Trump and Haley traverse the primary landscape, vying for the Republican presidential nomination state by state, Trump's firm hold on a significant faction of the party is evident.

WASHINGTON, Feb. 25 (Xinhua) -- Former U.S. President Donald Trump on Saturday secured victory over Nikki Haley, his former ambassador to the United Nations, in South Carolina's Republican primary, advancing a step closer to a potential face-off with incumbent Joe Biden in the upcoming presidential election in November.

Despite her aspirations to regain momentum after three losses in Iowa, New Hampshire and Nevada, Haley -- South Carolina's first female governor from 2011 to 2017 -- got roughly 40 percent of the vote, trailing Trump by approximately 20 percentage points.

As Trump and Haley traverse the primary landscape, vying for the Republican presidential nomination state by state, Trump's firm hold on a significant faction of the party is evident.

However, he remains embroiled in controversies surrounding his efforts to overturn the 2020 U.S. presidential election results and his alleged role in inciting the Jan. 6 Capitol Riot.

Meanwhile, despite growing inner-party pressure to drop out and allow Republicans to unite around Trump, Haley vowed she was "not giving up this fight."

"We're getting around 40 percent of the vote. That's about what we got in New Hampshire, too. I'm an accountant. I know 40 percent is not 50 percent. But I also know 40 percent is not some tiny group," Haley told supporters in her election-night remarks.

"In the next 10 days, another 21 states and territories will speak," she said. Her next station is Michigan, and then Super Tuesday on March 5, when 15 states and one territory will vote to choose candidates to compete in the general elections.

Voters cast their ballots at a polling station during the South Carolina Democratic presidential primary in Charleston, South Carolina, the United States, Feb. 3, 2024. (Photo by Andrew Whitaker/Xinhua)

Trump, who has swept all the early states, has contended that the Republican primary election was effectively over. "This was a little sooner than we anticipated," he said in his victory speech in Columbia in South Carolina, adding that he had "never seen the Republican Party so unified as it is right now."

A Marquette Law School national poll of registered voters conducted from Feb. 5 to 15 showed that Haley could hold a larger lead over Biden than Trump in a hypothetical general election match-up, considering "her strength with Republicans combined with an ability to attract more Democratic and independent voters than does Trump."

But most observers believe Trump's leadership in the party can hardly be shaken, and more discussion has been switched to who Trump's election partner will be. A Morning Consult tracking poll conducted from Jan. 23 to Feb. 4 showed Trump is considerably ahead in every major Super Tuesday state.

A daughter of Indian immigrants, Haley, 52, who portrays herself as a leader from "a new generation" and attacks Trump about his age and records in making America "chaos," has aimed to court independent voters and moderate Republicans.

But that strategy appeared to be ineffective. In the first Republican primary in Iowa, Trump secured over 50 percent of votes, while Haley even placed behind Florida Governor Ron DeSantis, previously considered a promising right-wing challenger to Trump who later withdrew.

Voters walk up the stairs to vote at a polling station during the South Carolina Democratic presidential primary in Charleston, South Carolina, the United States, Feb. 3, 2024. (Photo by Andrew Whitaker/Xinhua)

Then, in New Hampshire on Jan. 23, a significant battleground state where the governor Chris Sununu had endorsed Haley, she lost by roughly 9 percentage points.

In the recent Nevada contest, featuring both a state-run primary and a party-run caucus, only the caucus results dictated delegate allocation. Having chosen to participate in the primary, Haley was consequently excluded from the caucus. She suffered a significant setback, losing the primary to the "none of these candidates" option by a considerable 30 percent margin. Trump's name was not on the ballot. The outcome underscored her formidable challenge in securing the nomination.

The odds are against her, even in some of her targeted groups. For instance, according to an ABC News poll, even among college-educated voters, where Haley has experienced the greatest growth of support, she's trailing Trump by about 30 points nationally.

"Trump has established a powerful, identity-based relationship with his most dedicated supporters, and his opponents in the GOP have generally been unwilling to challenge this," Christopher Galdieri, a political science professor at Saint Anselm College in the northeastern state of New Hampshire, told Xinhua.

Haley and her campaign have shown no sign of relenting. Calling the election "a building situation," she said in an NBC interview that she did not necessarily need to win her hometown but had to do better than she did in New Hampshire, which was better than she did in Iowa.

However, with the sizable 20 percent margin in South Carolina, her pathway appears increasingly challenged.

Now, put aside the slim hope that Haley turns the tide; there's just one problem left in Trump's nomination: Will the former president, who is beset with 91 criminal charges across four criminal cases, including the Jan. 6 Capitol Riot in which many view him as an insurrectionist, be disqualified from the ballot?

Not likely, but the final answer primarily lies in an awaited ruling by the U.S. Supreme Court in response to a challenge from the western state of Colorado. The Colorado Supreme Court -- all seven of its justices appointed by Democratic governors -- ruled in December that Trump would be kicked off the ballot for engaging in what has been labeled an attempt to overthrow the government on Jan. 6, 2021. Then Trump appealed.

Former U.S. President Donald Trump (2nd L, Front) sits in the courtroom during his civil fraud trial at New York State Supreme Court in New York, the United States, on Oct. 18, 2023. (Doug Mills/Pool via Xinhua)

It is unclear when the Supreme Court, with a 6-to-3 conservative majority, will issue the ruling after hearing oral arguments in the appeal on Feb. 8. But the justices across the political spectrum have expressed concern over the possible ripple effect if Colorado's decision is upheld.

Brookings Institution senior fellow Darrell West told Xinhua: "Several justices expressed doubt about the effort to disqualify Trump from the presidential ballot ... They say it sets a precedent of allowing an individual state to outlaw particular candidates."

Formal challenges to Trump's presidential candidacy have been filed in at least 36 states and Colorado and Maine, which will both hold primaries on Super Tuesday, disqualified him from primary ballots, according to the New York Times. Trump appealed in both.

The lawsuits surrounding Trump's mishandling of sensitive government documents and cover-up payments to a porn star during the 2016 presidential campaign have been used as bargaining chips for both sides. Haley said Trump was a source of chaos and "all of this chaos will only lead to more losses for Republicans up and down the ticket." Meanwhile, Trump has long presented himself as a victim of political persecution and a challenger to the justice system, a move resonating with his supporters.

The cases are expected to unfold over the coming months during the general election, while Trump and his team have been trying to delay trials. In its latest development, New York Supreme Criminal Court judge Juan Merchan said last week he planned to begin the hush-money trial on March 25.

"Haley is staying in the race in case something happens in the court cases that shake confidence in him. She is counting on a conviction knocking him out of the race," West told Xinhua.

On the Democratic side, Biden is similarly dominating the field while facing challenges such as his age and health, disputes over his management of the U.S.-Mexico border and declining support among black voters.

The primary elections will be followed by Republican and Democratic conventions in July and August, in which each party will formally choose their presidential candidate. The candidates will participate in three televised debates before the voting day on Nov. 5.