NEW YORK — She's running.

U.S. Sen. Kirsten Gillibrand told a national audience on "The Late Show with Stephen Colbert" Tuesday she plans to run for president in 2020 — which, if successful, would make the Albany native the first woman ever to hold the nation's highest office.

She's now one of five potential Democratic candidates looking to challenge and unseat President Donald Trump next year.

"I'm forming an exploratory committee for president of the United States — tonight," Gillibrand, 52, of Brunswick, told Colbert during an appearance on the CBS show, which is filmed in Manhattan. The program will air at 11:30 Tuesday.

Asked by Colbert why she was running, Gillibrand said, "Because as a young mom, I'm going to fight for other people's kids as hard as I would fight for my own."

She cited expanding access to health care ("a right, not a privilege"), better educational opportunities and job training as three key issues.

"But you are never going to accomplish any of these things if you don't take on the systems of power that make all of that impossible — which is taking on institutional racism, it's taking on the corruption and greed in Washington, it's taking on the special interests that write legislation in the dead of night," she said. "And I know that I have the compassion, the courage and the fearless determination to get that done."

Gillibrand's announcement comes on the heels of her campaign representatives signing a lease for 4,000 to 5,000 square feet of space in the Frear Building in Troy at 2 Third St. She hired her Senate chief of staff, Jess Fassler, and Meredith Kelly, a former spokesperson for Sen. Charles Schumer and communications director for the Democratic Congressional Campaign Committee, to work on her nascent campaign.

The appearance on Colbert's show kicks off a week that will take the senator from New York City to Troy to Iowa, site of the all-important caucuses a year from now.

On Wednesday, Gillibrand, her husband Jonathan and their sons Theo and Henry will appear at the Country View Diner on Hoosick Street to have brunch with family and friends and speak to reporters.

On Friday, she's set to arrive in Sioux City, Iowa, to make her first public appearance. Her stops in Iowa will include Boone, Ames and Des Moines, and wrap up Sunday in Cedar Rapids.

"What is the first thing you would do on Day One in office?" Colbert asked Gillibrand.

"Well, the first thing that I would do is I would restore what's been lost — the integrity and the compassion of this country," Gillibrand replied.

She said she would bring people together. She noted she sponsored legislation with nearly every Republican senator, including an anti-sexual harassment bill with Ted Cruz.

"Thank you for believing in something so much you were willing to work with Ted Cruz," Colbert cracked.

Asked how to end the government shutdown, now 25 days and going, Gillibrand pinned it squarely on Trump.

"What he has done is absolutely outrageous," Gillibrand said. "He created the problem himself. He created the crisis himself and he shouldn't be having a temper tantrum because he can't get what he wants ... shutting down the government is hurting people. Right now he's doing it because he wants his own way. If you're going to do something like that, you better be fighting for other people, not yourself."

In a lighthearted dig, Colbert reminded the senator of her propensity for four-letter words.

"Everybody knows you like to swear. Are you going to swear on the campaign trail?" Colbert asked Gillibrand, noting the campaign could be stressful.

"I'm gonna definitely try," Gillibrand replied.

"What's the word you'll miss the most?" Colbert pressed.

"It rhymes with duck," Gillibrand answered.

Colbert gave Gillibrand some parting gag gifts for states where she will campaign early on — an ear of corn for Iowa, granite from New Hampshire, mustard barbecue sauce for South Carolina. He also gave her plane ticket for Michigan so Gillibrand will remember to campaign there — a dig at Hillary Rodham Clinton, who lost the state to Trump.

A Gillibrand campaign official, speaking on condition of anonymity, said that the campaign is predicated on the notion that "The lesson of 2018 is that the future of the Democratic Party is with women."

The official provided statistics saying that 58 percent of women say they are paying more attention to politics since the election of Trump, a statistic that is reflected in stepped-up participation by women running for and winning seats in Congress.

"They contributed, volunteered, voted, ran for office, and won," the official said.

Gillibrand's campaign slogan is simple: "Now is our time."

The candidate raised more than $27 million in the 2018 cycle and has more than $10.5 million in the bank — a sum her campaign called the third-highest total of all declared or potential 2020 contenders.

Gillibrand supported action to combat climate change, gun violence, sexual assault and abuse in the military and on college campuses — a record that her campaign called the "most solidly anti-Trump voting résumé of any U.S. senator."

The senator's 2018 Republican opponent, businesswoman Chele Farley, was relentless in accusing Gillibrand of secretly holding presidential ambitions. In their lone debate, Farley managed to get the Democrat to state that, if re-elected, "I will serve my six-year term."

Two weeks later — after hammering Farley on Election Day by a 2-to-1 margin — Gillibrand appeared on Colbert's show to say that she was seriously considering a presidential run that would render her earlier statement inoperative.

It is not the first time Gillibrand has adjusted her previous stances, though not in such a brief span of time. Critics on the left and right have pointed to her shift leftward on issues included immigration and gun control — changes that corresponded with her ascension from regional congresswoman to statewide senator.

More recently, she took heat from some progressives for her decision to call for the resignation of U.S. Sen. Al Franken, D-Minn., in late 2017 following numerous allegations of inappropriate behavior toward women. Gillibrand's action was followed by an avalanche of Democratic calls for Franken's exit, and he quickly announced his departure.

Gillibrand has deep political roots locally. She is the granddaughter of the late Dorothea "Polly" Noonan, the longtime confidante of late Albany Mayor Erastus Corning 2nd. Noonan, who led the Albany County Democratic Women's Club, mobilized women to support Democratic candidates in the old Albany political machine.

Gillibrand, who attended the Emma Willard school in Troy, is the daughter of Douglas Rutnik, an attorney and lobbyist, and Polly Rutnik, also a lawyer. A graduate of Dartmouth College and UCLA law school, she is a lawyer whose résumé includes work for then-federal Housing Secretary Andrew Cuomo and at the New York City firm of Boies, Schiller & Flexner.

Cuomo, beginning his third term as New York's governor, has been mentioned as a potential Democratic candidate for president, though he has denied holding any interest.

Gillibrand defeated former U.S. Rep. John Sweeney, a Republican, in 2006. In 2009, Gov. David Paterson appointed her to fill the Senate seat left vacant after Sen. Hillary Rodham Clinton was nominated for secretary of state by President Barack Obama.

"Kirsten Gillibrand is appealing to Americans because she represents so much what our generation is fighting for her," said Albany Commissioner of Administrative Services Rachel McEneny, who worked for Gillibrand from 2007 to 2011 and got to know the contender while they logged thousands of miles together.

"She listens, she's thoughtful, she has empathy, she understands federal government when it's broken," McEneny said. "She is extremely hard-working and tenacious.

McEneny noted Gillibrand has lived in New York City, Los Angeles and China but has embraced smaller communities by living near Hudson and Troy.

"She had a gift of connecting with people, and I believe it's from being a good listener," McEneny said. "You hear people she has spoken to and their words come out in her speeches. I hope she runs, she represents a lot of what I would like to hear as an American and I think in that she is someone who will create a better country for my daughter."

Other candidates in the race to unseat Trump include Sen. Elizabeth Warren, D-Mass., former federal housing secretary and San Antonio Mayor Julian Castro; and Rep. Tulsi Gabbard of Hawaii. Sens. Cory Booker of New Jersey and Kamala Harris of California are seen as imminent entries in the contest.

Former Vice President Joe Biden has indicated interest if no viable Democrat emerges.