(Bloomberg) -- New York Mayor Bill de Blasio is heading straight to the campaign trail Thursday following a morning television appearance where he’s expected to announce that he’s making a bid for the 2020 Democratic presidential nomination.

He is scheduled to appear on ABC’s “Good Morning America” program and then fly to Iowa, where caucuses next February will formally kick off the nomination contest. He’s following that with a trip Saturday to South Carolina, another crucial early voting state.

NBC News reported on Wednesday that de Blasio would declare his bid on Thursday, citing an unnamed campaign spokesperson. Olivia Lapeyrolerie, a spokeswoman for de Blasio, declined to comment.

A Facebook post by the Democratic organization in Iowa’s Woodbury County offered a welcome to the new candidate: “Come meet NYC Mayor Bill de Blasio and First Lady Chirlane McCray.”

De Blasio, who was first elected mayor in 2013 after serving as the city’s public advocate, becomes the 23rd active candidate for the Democratic presidential nomination. His campaign will underscore his advocacy of major investments in education and health care, warnings about income inequality. His high profile as the leader of the largest U.S. city could make his candidacy stand out in a very crowded field of people competing to challenge President Donald Trump in November 2020.

The race has been re-shaped by the presence of former Vice President Joe Biden, who has emerged as the front-runner since he announced his candidacy on April 25. Yet still more Democratic politicians have entered the contest since then, most recently Montana Governor Steve Bullock earlier this week.

De Blasio’s decision to run reverses a vow made in 2017 during a televised debate as he campaigned for a second term, when he looked straight at the camera and declared: “I will serve for four full years.” He began backtracking from that promise in January, when he told reporters, “the world has changed in the last couple of years.”

The message de Blasio’s presidential campaign intends to sell is a vision of New York as a successful city, with high employment, improved high school graduation rates and low crime.

His six years running City Hall have been a mixture of success and failure.

Both were on display earlier this year when Amazon.com Inc. chose Long Island City in Queens for a second headquarters -- then abruptly withdrew amid a fierce local backlash, chiefly over subsidies that had been offered to the company. The mayor and New York Governor Andrew Cuomo, a political rival, came under harsh criticism for conducting negotiations in secret, and then failing to salvage the deal.

The de Blasio administration created a universal pre-kindergarten program that now serves 70,000 students, and has embarked on a pre-school plan for 3-year-olds. A two-decade trend of decreasing crime has brought reports of murder and shootings to levels not seen since the 1960s.

And de Blasio and Cuomo earlier this year joined forces to win passage in the state Legislature of a congestion pricing plan that would charge motorists to drive in parts of Manhattan at peak times, and use the revenue to promote mass transit.

(Updates with de Blasio’s record as mayor, in final two paragraphs. An earlier version corrected the timing of his trip to South Carolina.)

To contact the reporter on this story: Henry Goldman in New York at hgoldman@bloomberg.net

To contact the editors responsible for this story: Joe Sobczyk at jsobczyk@bloomberg.net, John Harney

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