Former Hewlett-Packard Co. CEO Carly Fiorina said Monday she will seek to become the United States' first female president, joining a crowded field for the Republican nomination.

“Yes, I am running for president,” Fiorina said on ABC's Good Morning America, adding she'd be the best person for the job because she understands how the economy, the world, and technology work. 

The primary race already includes a trio of U.S. senators who have announced their candidacy: Ted Cruz of Texas, Rand Paul of Kentucky, and Marco Rubio of Florida. Retired neurosurgeon Ben Carson joined the race on Sunday, and former Arkansas Governor Mike Huckabee is expected to enter the race on Tuesday.

After her announcement, Fiorina was set to speak to the media on a conference call and take questions on the livestreaming app Periscope, according to spokeswoman Anna Epstein. Later this week, Fiorina is set to speak at a TechCrunch event in New York, then swing through the key early-voting states of Iowa, New Hampshire, and South Carolina, Epstein said.

Fiorina, who never has held elected office, served as an executive at AT&T and Lucent before assuming the leadership role at HP, then America's largest computer maker, in 1999. That business experience, along with her leading role at a number of charitable organizations—such as the micro-financing non-profit Opportunity International and Good360, which helps coordinate corporate donations—will serve as a centerpiece of a campaign that is expected to portray Fiorina as the antithesis of the career politician, and the only Republican who can neutralize Democratic frontrunner Hillary Clinton's advantage among women voters. 

“We have to have a nominee who can take punches, but we have to have a nominee who will throw punches,” Fiorina told the National Review Ideas Summit on Saturday. “We’ve got to take that fight to Hillary Clinton.”

On Monday, Fiorina was quick to attack Clinton after making her announcement. “I have a lot of admiration for Hillary Clinton, but she clearly is not trustworthy. She has not been transparent about a whole set of things,” including the 2012 Benghazi attack, her private e-mail server, and her family foundation's foreign contributions, Fiorina said.

Also on Bloomberg Politics: The Definitive Carly Fiorina Scouting Report, by Mark Halperin and John Heilemann

Fiorina, 60, routinely cites her corporate experience and lack of government jobs in the months leaning up to her announcement. “People who have been in politics all their lives are somewhat disconnected from the rest of us,” she told reporters at a Christian Science Monitor breakfast in April.

Her greatest corporate achievement, her rise to lead one of the country's most-prominent tech companies, is also something of an Achilles' heel, as the HP board ousted her in 2005. A merger with rival Compaq that Fiorina oversaw led to earnings stagnation, massive layoffs, and a plunging stock price for HP.

Also on Bloomberg Politics: What Brought Carly Fiorina Down at HP Is Her Greatest 2016 Asset

During Fiorina's only attempt at seeking elected office, in the 2010 California Senate race, incumbent Barbara Boxer repeatedly criticized her record at the company. Boxer ended up winning by double digits.

In the months leading up to her presidential announcement, Fiorina has worked to position herself as one of Clinton's fiercest critics, noting her gender offsets one of Clinton's perceived advantages. 

“If Hillary Clinton were to face a [Republican] female nominee, there are a whole set of things that she won’t be able to talk about,” Fiorina said at the April Christian Science Monitor breakfast. “She won’t be able to talk about being the first woman president. She won’t be able to talk about a war on women without being challenged. She won’t be able to play the gender card.”

In January, speaking at the Iowa Freedom Summit, Fiorina rolled out what has become an applause line.

Carly Fiorina to HRC: `Name an Accomplishment'

“Like Hillary Clinton, I too have traveled hundreds of thousands of miles around the globe,” she said. “But unlike her, I have actually accomplished something. Mrs. Clinton, flying is an activity, not an accomplishment.”

Politically, Fiorina is a small-government conservative who, like many in her party, favors a host of tax cuts. She has supported building the Keystone XL pipeline while opposing cap-and-trade measures meant to curb greenhouse gas emissions. A strong gun-rights supporter, Fiorina has criticized 1994's assault weapons ban.

“I support the Second Amendment and the NRA [National Rifle Association] not because I'm a hunter, or even a skeet shooter—I'm not,” Fiorina said in a taped address to the gun lobby's 2015 annual convention. “And while I've never had to protect my home or my family from an intruder, I'm glad I can if I ever have to.”

Fiorina opposes abortion and favors overturning the Supreme Court's Roe v. Wade decision. She does, however, allow for exceptions in cases of rape or incest. On gay rights, she says she voted in 2008 in support of California's Proposition 8, which banned same-sex marriage in the state until it was struck down in the courts. At the same time, she does favor civil unions, and would extend government benefits to same-sex couples bound by them. 

Also on Bloomberg Politics: The Definitive Carly Fiorina Scouting Report, by Mark Halperin and John Heilemann

In 2008, Fiorina was diagnosed with breast cancer and underwent chemotherapy, radiation therapy, and a double mastectomy. Now cancer-free, she lives in Northern Virginia with her second husband, Frank, a former AT&T executive whom she married in 1985. While Fiorina has no biological children of her own, she helped raise Frank's two daughters from a previous marriage. 

The author of two memoirs, 2007's Tough Choices, and 2015's Rising to the Challenge: My Leadership Journey, Fiorina was born in Austin, Texas, before going on to high school in London, England, and Durham, N.C. She holds a bachelor's degree in philosophy and medieval history from Stanford University, an MBA in marketing from the Robert H. Smith School of Business at the University of Maryland-College Park, and a master's of science in management from the MIT Sloan School of Management.

Fiorina thus far has polled in the low to middle ranks of potential GOP candidates. A Bloomberg Politics national poll in April found that 7 percent of Republicans or independents said they would seriously consider supporting her, while an additional 31 percent said they might consider her. But 35 percent said they would never consider supporting her candidacy.

—Ben Brody contributed to this report.

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