She stands out on the campaign trail for talking frequently about foreign policy issues, and she is the highest-polling Republican who supports further involvement in the Ukraine war.

Here are some facts about Haley's life and political career:

DAUGHTER OF IMMIGRANTS

Haley, 51, has gained a reputation in the Republican Party as a solid conservative who has the ability to address issues of gender and race in a more credible fashion than many of her peers. At the same time, she has drawn criticism for her ambiguous positions on some major policy issues.

She is the daughter of two immigrants from India who ran a clothing store in rural South Carolina, and has spoken occasionally about the discrimination her family faced.

Haley graduated from Clemson University in 1994 with a degree in accounting, and helped expand her parents' clothing business. She took on leadership roles in several business organizations before winning a seat in the South Carolina state legislature in 2004. She is married and has two children.

SOUTH CAROLINA GOVERNOR

Elected governor of South Carolina in 2010, Haley became the first woman to hold that post in the Deep South state and the second person of Indian descent to serve as a state governor in the United States.

She received national attention in 2015 when she signed a bill into law removing the Confederate battle flag from the grounds of the South Carolina state capitol following the murder of nine black churchgoers by white supremacist Dylann Roof.

She also appointed a current rival in the Republican presidential nominating contest, Tim Scott, to the U.S. Senate in 2012.

UNITED NATIONS AMBASSADOR

Haley endorsed several rivals to Trump in the 2016 Republican presidential nominating contest, and occasionally tangled with him during the primaries.

But she then went on to serve as his ambassador to the United Nations, where she gained a reputation as a vocal defender of U.S. interests. During that time, the United States pulled out of the Iran nuclear deal, which was unpopular with Republicans.

2024 PRESIDENTIAL CAMPAIGN

Haley was among the first candidates to enter the race, throwing her hat into the ring in February.

While she enjoyed a brief bump in opinion polls, she subsequently languished in the mid- and lower single digits in most national and state-level surveys, until the August debate gave her a modest but measurable boost. She still has just a fraction the support of Trump, but multiple polls show her in second place in New Hampshire and South Carolina, key states in the Republican nominating process. She will be hoping the second debate on Wednesday further raises her profile.

She has tried to distinguish herself as the most capable contender on foreign policy. While almost all have staked out a tough position on China, Haley's unabashed support for Ukraine represents a contrast with Trump and Florida Governor Ron DeSantis, who both say the conflict is not central to U.S. national security.

RELATIONSHIP TO TRUMP

Since leaving the Trump administration in 2018, Haley has distanced herself from him several times, only to later soften her rhetoric.

She criticized Trump after his supporters attacked the U.S. Capitol on Jan. 6, 2021, in an attempt to overturn his 2020 election loss to Democrat Joe Biden, but later sought to make amends with him.

She has mainly dodged questions pertaining to Trump's four state and federal indictments since leaving office.

She did, however, criticize Trump after his indictment this summer for mishandling sensitive national security information, saying that if the information laid out in the indictment is true, it is "incredibly dangerous to our national security."

She has said she has several policy differences with Trump, notably with respect to China, North Korea and Ukraine.