U.S. Sen. Cory Booker made his debut as a potential 2020 presidential contender, arriving in Iowa on Saturday -- just hours after casting his Senate vote against Supreme Court nominee Brett Kavanaugh.

The New Jersey Democrat was well-received at an Iowa Democrats' gala in Des Moines, which featured around 1,400 activists in a state where Republicans control the governorship and both chambers of the Legislature, the Washington Post reported.

His visit is the first by a Democrat who is considered a top-tier candidate for the 2020 presidential election. He planned to stay in the state through Thursday.

A spokesman for Booker, Jeff Giertz, insisted the senator has not decided to run for president and is focused purely on the midterm elections.

Giertz added that Booker has campaigned in 20 states with the intention of supporting Democratic candidates who will be a check and balance against the actions of President Trump.

During his 45-minute speech, Booker compared the anguish many felt over Kavanaugh’s confirmation to when he watched a man die from a gunshot wound.

“Hope is the act of conviction that despair can never have the last word,” he said. “We’re not defined in this state by Republicans in power; we’re defined by how we respond to them. We’re not defined by a president who mocks a hero, Dr. [Christine] Blasey Ford. We’re not defined by a president who doesn’t believe women.”

Booker threw himself in the national spotlight during the Kavanaugh confirmation hearings when he made public some documents that the Senate Judiciary Committee intended to keep secret, risking expulsion from the Senate.

He also drew criticism at the same time when he infamously said, “This is about the closest I’ll probably ever have in my life to an ‘I am Spartacus' moment."

On Saturday, he drew four standing ovations, mostly as he quoted a speech given by Martin Luther King Jr. on the 1965 Voting Rights Act in Selma, Ala.

“How long? Not long! Until we answer the president’s hate with our universal love,” Booker said. “How long until November? Not long!”

Afterward, he declined to answer questions from reporters about Trump’s speech in Topeka, Kan., earlier in the day, where the president criticized Booker’s tenure as mayor of Newark.

“I have nothing personal against the president,” said Booker. “If he wants to attack me personally, he can. If he wants to attack my record, the reality is that the people of New Jersey elected me statewide, and I’m proud of the work we did. I’ll never let him pull me so low."

Booker has made inroads with influential Iowa Democrats, such as Des Moines lawyer Jerry Crawford, a veteran Democratic power broker who was a leading adviser to Hillary Clinton's 2008 and 2016 campaigns.

He is the only top-tier presidential prospect to appear in the state ahead of the midterm elections, giving him time to introduce himself to voters before other candidates show up.

Other big-name Democrats have stayed clear of Iowa so far, according to the Des Moines Register.

“I’m aware of Sen. Booker,” said Nathan Thompson, a Democratic chairman in Winneshiek County. “He definitely seems like he has presidential ambitions. But I’m not real familiar with him, beyond being the former mayor of Newark.”

On Sunday, Booker will headline a fundraiser for Deidre DeJear, the Democratic nominee for Iowa secretary of state

He will also headline another Democratic fundraiser later this month in South Carolina. Working to build his profile, he recently appeared on the “Tonight Show” and was profiled in a New York magazine article last month.

The Associated Press contributed to this story.