April 2, 2012 -- There is a wooden sign posted on South Carolina Gov. Nikki Haley's statehouse office door: "Can't is not an option."
Haley has broken many barriers in the state. She is not only its first non-white governor, but also its first female and, elected at 38, its youngest. She touts the phrase as a defining idea for her administration. It is even the title of her new book.
At an interview at the governor's mansion in Columbia, S.C., Haley told "Nightline" the sign has been there since day one of her administration.
"I want everyone who comes in -- staff, legislators, constituents -- to know from the outset that's how things work here," she said.
It can make her a tough boss at times she admits, but, she says, an effective one.
Watch the full interview with Gov. Nikki Haley on "Nightline," Tuesday, April 3 at 11:35 p.m. ET/PT
A Tea Party favorite endorsed by Sarah Palin during her gubernatorial race in 2010, Haley's endorsement in the Republican primary was a highly coveted one. The South Carolina governor came out early for Mitt Romney, criss-crossing the state with him in the weeks before the state's January primary.
Despite her stalwart campaigning on his behalf, Haley claims she has no interest in being his running mate. If offered the vice presidential slot, Haley said she would not take it.
"I'd say, 'Thank you, but no,'" she said. "I made a promise to the people of this state. And I think that promise matters. And I intend to keep it."
But the governor fell short of delivering a South Carolina win to Romney. Instead the GOP presidential candidate suffered a substantial defeat in the Palmetto state, falling 13 percentage points behind Newt Gingrich.
Haley brushed off Romney's loss.
"South Carolinians are strong, independently-minded people," Haley said. "At the end of the day, they make their own decisions. And I respect them for that. And I welcome that. And I told him that from the very beginning."
Haley said she "can sleep at night" after his loss, because she still thinks Romney is "the one" who will get the nomination and is best positioned to beat President Obama.
She rejects the idea that her party is waging a "war on women," an accusation that many women's rights activists have levied at the Republican Party following its opposition to the government mandating that contraception be covered under insurance plans.
"The public likes to think that women only care about contraception," Haley said. "Contraception doesn't define a woman. That's -- doesn't define our views. We're so much smarter and broader than that."
The governor bristles at the thought of being called a "feminist," which she deems "a hard word."
"I think any label is bad," Haley said. "I'm more than a label. I am Nikki Randhawa Haley, who was born and raised in Bamberg, who is the proud wife of an officer in the military, and the very proud -- mother of two children.
"That's who I am," she added. "If you want to label me, label me that."
In a state where the confederate flag still flies at the state house, convincing Southerners to accept a young, female Indian-American as their governor proved challenging.
"I had a white senator call me a rag head, and I had an African-American legislator call me a conservative with a tan," Haley said.
During her gubernatorial campaign rumors emerged that she had participated in two extra-marital affairs, allegations Haley said were "flat-out lies."
As soon as the stories broke, Haley said she got a call from her friend and supporter Sarah Palin encouraging her to fight.
"It's not just a Nikki issue. It's a Sarah issue," Haley said. "It's a lot of us that go through this. But it is what we sacrifice to bring good government. It's what we sacrifice to change our states and our country."
Haley says she channels her friend Palin's feistiness when under attack by her opponents.
"I wear heels," the South Carolina governor said. "It's not for a fashion statement, it's ... ammunition."
And those campaign fires didn't die after she won the state house. The latest poll numbers show her approval rating is hovering around 35 percent. But Haley is not planning to stop fighting.
She points to the state's improving unemployment rate, which was 12 percent when she was running for office and 10.5 percent when she took over as governor. On Friday it ticked down to 9.1 percent. That's still one percentage point higher than the nation, but Haley was upbeat: "There is more work to be done, but we are moving in the right direction."
She is proud, she said, that since taking office 22,000 new jobs have come to South Carolina.
"We build things in South Carolina now," Haley said. "We build planes. We build cars. We build tires."
Though Haley has closed the door on having her name on the presidential ticket this year, she left it ever so slightly ajar about running for president herself in 2016.
"I don't know -- I mean life has surprised me constantly," Haley said when asked if she'd run in four years. "But that's not anything I can imagine.
"This is what I want to do," the governor added. "So do I want to think about anything in the future? No. Why ruin where I am now?"