Cory Booker's half-full kickoff rally could be miserable news for the future of his campaign

• Sen. Cory Booker's 2020 kickoff rally on Saturday had fairly low turnout, especially compared to some of his Democratic competitors.
• Newark police were reportedly preparing for around 10,000 people, but just over 4,100 showed.
• Booker's campaign has struggled to find momentum so far, and he's way behind in both the polls and fundraising.
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NEWARK, NJ - The weather was perfect for Democratic Sen. Cory Booker's 2020 kickoff rally in Newark, New Jersey, on Saturday, but the sunshine was apparently not enough of a draw for locals to come out and support their former mayor.

Newark police were reportedly planning for up to 10,000 people to show up at the rally. The venue, Military Park in the city's historic downtown, was full of open space.

Booker's campaign told INSIDER that according to Gary Bootes, head of security for the event, there were over 4,100 people in attendance.

Comparatively, Sen. Bernie Sanders' 2020 kickoff rally in Brooklyn, New York, which took place on a snowy, cold day in early March, had a crowd of roughly 13,000.

Sen. Kamala Harris's 2020 kickoff rally in Oakland, California, in late January had approximately 20,000 people in attendance.

Though the crowd in Newark was relatively small, it was quite diverse. The city's population is roughly 50% black, and the crowd at the rally was full of people of all races and ages.

Those in attendance did their best to find shade where they could on one of the warmest days in the region in 2019 so far. At least one person fainted but got help quickly from medical professionals on the scene.

Before Booker took the stage, his mother, Carolyn, spoke and boasted of her son's accomplishments.

"I have watched Cory fight for this community. I have watched Cory fight for this state," she said. "He's a servant leader…Cory will be the type of president who doesn't just lead people, but will listen to the people."

Booker strutted onto the stage around 1:30 pm ET to Bill Wither's "Lovely Day," thanked his mother, and soon thereafter declared, "I learned right here on these streets that you can't make progress by dividing people."

"I will be a president for all people in America," Booker went on to say in English, and also in Spanish, in what was perhaps a veiled jab at President Donald Trump and his anti-immigrant rhetoric.

Later, Booker said, "Unlike this president, I won't ignore, or give license to white supremacy."

The New Jersey senator accused Trump of squandering "America's moral authority" and coddling dictators.

"We will no longer wait for America to stand up for justice around the world," he said.

As he wrapped up his speech, Booker urged the crowd to recognize the urgency of the times we live in.

"America we know our history - it is perpetual testimony to impatient, demanding, unrelenting people who in every generation stand up for justice. Generations of Americans have shown us what was possible when they refused to wait. Now it's our turn. And we have work to do. America - we can't wait. - we will not wait... Together, America, we will rise," Booker said, his voice rising as he delivered the final lines of his address.

The crowd cheered and Booker walked off to "No Problems" by Chance the Rapper. After, he could be seen taking selfies and chatting with people in attendance, though most of the crowd quickly dissipated.

Despite Booker's strong rhetoric, his campaign appears to be struggling to find itself. The New Jersey senator is way behind in the polls - the latest Morning Consult poll puts him in seventh place.

He's also getting crushed in fundraising. He raised $5 million in February and March, his campaign recently announced - far below other 2020 candidates like Sen. Sanders and Sen. Harris, who respectively raised about $18.2 million and $12 million in the same general period.

Despite starting off with a far stronger national profile, Booker is even getting outpaced in polling and fundraising by Mayor Pete Buttigieg of South Bend, Indiana.

It's still early in the 2020 race, and Booker's campaign could get a boost if he performs well in upcoming debates in Miami and Detroit. But, so far, his run for the White House has received a lukewarm response from Democratic voters.