Who is Cory Booker, the Democrat from New Jersey holding the Senate floor?

Sen. Cory Booker, who took hold of the Senate floor Monday night and held onto it Tuesday as he railed against President Donald Trump’s Republican agenda, once found common ground with the president during his first term.

Booker, a New Jersey Democrat who ran an unsuccessful presidential campaign in 2020, expressed frustration bordering on exasperation at a host of Trump issues in his long Senate speech — from the possibility of annexing Greenland and Canada to slashing social programs and cutting taxes.

Booker’s speech, occasionally interrupted by Democratic colleagues to whom he yielded for questions while catching his breath, came as Democrats are in the minority in the Senate and the House. It’s unclear what effect Booker’s speech could have, but it reflects one of the levers available to out-of-power parties.

Here’s a closer look at who Booker is and what he’s been saying:

STORY: Sen. Cory Booker delivers marathon speech to protest President Trump policies

Who is Booker?

Booker, 55, was born in Washington, D.C., and moved to northern New Jersey when he was a boy. He’s spoken about growing up in a Black family in a predominantly white neighborhood and how his parents faced opposition when they tried to buy a house.

He played football in college at Stanford University before attending Yale Law School and then worked as an attorney in nonprofits, giving legal aid to poorer families. Elected to the Newark City Council and then as mayor of the state’s biggest city, he served there until 2013.

His time in office coincided with Facebook founder Mark Zuckerberg’s $100 million donation to the city’s public schools, a boon that burnished his status as a Democratic rising star at the time.

In 2013, he was elected in a special election to the U.S. Senate after the death of incumbent Frank Lautenberg. He then won his first full-term in 2014 and was reelected in 2020.

He launched an upbeat but ultimately doomed 2020 bid for president in a crowded Democratic field. Standing in the front yard of his Newark house, Booker declared “love ain’t easy.”

What’s he talking about?

Booker’s Senate speech started about 7 p.m. Monday and carried through the night.

By Tuesday morning, his voice occasionally wavered with emotion as he recognized his colleagues who asked him questions, giving him a chance to take a break from speaking.

He read letters from constituents, cited authors like Langston Hughes and leaned into foreign policy and potential social safety net cuts.

He said Republicans’ budget language aimed to cut health care for Americans “to give tax cuts disproportionately to the wealthy” and would drive up deficits.

He said the U.S. was giving up leading the planet and cited Trump’s proposals to take over Greenland and Canada while feuding with longtime allies.

Reflecting his inclination toward uplifting rhetoric, Booker lamented a lack of unity.

“We are a union in trouble compared to our global peers,” he said. “Yet we are a nation of utter abundance, and we’ve proven in the past to be a nation of incredible vision.”

He also occasionally took aim at Elon Musk, the richest person in the world, who’s advising Trump and leading the Department of Government Efficiency. He criticized the president’s agenda to renew tax cuts that would benefit wealthy Americans, like Musk.

“I wish he would say the truth — I don’t need a tax cut,” Booker said.

What’s Booker done in Congress?

Booker played part in a 2018 bipartisan measure to overhaul federal sentencing laws passed after a few Black ministers, leaders and lawmakers forged an alliance with Trump, whom some had condemned as racist for the previous two years. The reforms aimed to create a path to freedom for hundreds of Black and Latino prisoners.

Among the bills he’s sponsored that became law was a 2019 measure that permitted states to transfer money from clean water revolving funds to drinking water revolving funds to address public health.

He chairs the Democratic Strategic Communications Committee and touts in his Senate biography that he sought to protect the Affordable Care Act from repeal.