CHICAGO - In what may be one of the last major speeches of his decades-long political career, President Biden on Monday night handed the reins of the party to Vice President Kamala Harris as he spotlighted their administration's accomplishments over the past three and a half years.

Speaking in front of a jam-packed United Arena, site of the Democratic National Convention, the president declared "America, I gave my best to you," as the crowd of party officials and delegates, activists, and supporters repeatedly gave Biden sustained ovations and chants of "thank you, Joe."

Praising his vice president, Biden said that "selecting Kamala was the very first decision I made before I became when I became our nominee, and it was the best decision I made my whole career."

"She's tough, she's experienced, and she has enormous integrity, enormous integrity. Her story represents the best American story," the president highlighted.

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And he asked the crowd are "you are ready to vote for freedom. Are you ready to vote for democracy and for America? Let me ask you, are you ready to elect Kamala Harris and Tim Walz, President and Vice President of the United States."

Biden repeatedly took aim at former President Trump and the threats he said the Republican presidential nominee posed to America's democracy and international alliances. And looking to his vice president and her running mate, Minnesota Gov. Tim Walz, he pledged to be "the best volunteer Harris and Walz have ever seen."

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Harris and Walz and their spouses, Second Gentleman Doug Emhoff and Minnesota First Lady Gwen Walz, joined the president, First Lady Jill Biden and their family, at the podium following Biden's address, in a clear sign of party unity.

The president's speech came four weeks and one day after his blockbuster announcement that he was ending his own White House bid and endorsing his vice president to replace him on the party's 2024 ticket in the election showdown against former President Trump.

Biden's disastrous performance against Trump in their late June debate fueled questions over whether the 81-year-old president had the physical and mental abilities to handle another four years in the White House and sparked a chorus of calls from within his own party to end his 2024 campaign.

Biden eventually caved to the pressure, announcing the suspension of his re-election campaign three days after the Republican National Convention ended with a solidified GOP ticket of Trump and running mate, Sen. JD Vance of Ohio. 

Biden spoke in front of a crowd that included plenty of politicians who publicly urged or maneuvered behind the scenes for the president to drop out of the race, as his support in public opinion polls began to fade following his debate showdown with Trump.

Since Harris succeeded Biden, the vice president has been riding a wave of energy, with a jump in polling and fundraising as the battle with Trump is once again a margin-of-error race.

As Harris has surged, Trump has increasingly attacked the Democrats for what he charged was "a vicious COUP" against Biden.

"Crooked Joe Biden was told, "Sorry Joe, you’re losing to Trump, BIG, and you can’t beat him - You’re Fired," the former president claimed Monday in a social media post.

But Biden in his speech aimed to dispel any notion that he was angry about changing course and giving up his bid for a second term in the White House.

"You see, it’s been the honor of my lifetime to serve as your president. I love the job, but I love my country more," Biden said. "And all this talk about how I’m angry [at] all those people who said I should step down — that’s not true."

With five months left in his presidency, the speech was not billed as a farewell address, but it did in some ways have the feeling of a swan song, as he touted his administration's accomplishments.

But Biden also pointed to the work he has left - including supporting Ukraine in its war against Russia and securing a cease-fire and hostage release deal between Israel and Hamas to end the deadly war in Gaza.

Outside the security zone surrounding the arena, anti-Israeli protesters marched throughout the day. And inside the United Center, a small group of delegates protesting Biden's handling of the war briefly held up a banner that read "stop arming Israel." But delegates quickly blocked them with "We Love Joe" signs and drowned them out. 

At one point, pointing to the rising death toll, Biden said the "protesters have a point." 

Speaking minutes before Biden at the convention podium was former Secretary of State, former senator, and former first lady Hillary Clinton, the Democrats' 2016 presidential nominee. 

Clinton, in her speech, blasted Trump, praised Biden, and said that Harris has the "character, experience and vision to lead us forward."

The speeches by Clinton and Biden - the party's two previous standard-bearers - symbolized how the Democrats old guard was passing the torch to a younger generation.

Harris, in a brief surprise appearance from the podium earlier in the evening, praised her boss.

"I want to kick us off by celebrating our incredible president," she emphasized. "Joe, thank you for your historic leadership, for your lifetime of service to our nation, and for all you will continue to do. We are forever grateful to you." 

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CHICAGO – The Democratic National Convention reportedly snubbed Teamsters President Sean O'Brien's request to speak during the convention, just weeks after his historic address before the Republican National Convention. 

"We have not received a response to our request to speak," the Teamsters told the National Desk on Monday of O'Brien's previous request to address the audience in Chicago. 

O'Brien had requested to address both the Republican National Convention and DNC around the same time earlier this year, ABC News reported last week, but only received a reply from the RNC. The Teamsters have historically endorsed Democratic candidates, but have remained neutral in its endorsement this election cycle. 

The labor union chief joined the RNC last month in Milwaukee, Wisconsin, where he did not offer an endorsement to former President Donald Trump, but spoke to the audience about "reaching across the aisle." 

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"Now, when I won the presidency of the Teamsters in a national election two and a half years ago, we started reaching across the aisle," O’Brien said during his speech. "In the past, the Teamsters have endorsed GOP candidates, including Nixon, Reagan, and George H.W. Bush."

"But over the last 40 years, the Republican Party has really pursued strong relationships with organized labor," O’Brien said. "There are some in the party who stand in active opposition to labor unions. This, too, must change."

O’Brien was the first Teamster in the organization’s 121-year history to speak at the RNC, which he underscored when he said during his speech: "Teamsters are here to say we are not beholden to anyone or any party."

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The speech, despite its lack of endorsement for Trump, sparked the ire of some liberal union members, as well as others within the Democratic Party. 

Teamster Vice President At-Large John Palmer, a member of the union since 1987, lambasted O’Brien’s decision last month, calling it "unconscionable for any Labor leader to lend an air of legitimacy to a candidate and a political party, neither of which can be said to have done or can be expected to do anything to improve the lives of the workers we are pledged to represent." 

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A handful of other union leaders are slated to speak during the DNC, with United Automobile Workers President Shawn Fain the only union chief addressing the audience in a solo speech. 

The Harris campaign and DNC leaders did not immediately respond to Fox News Digital's request for comment on reportedly snubbing O'Brien and his request to join the convention. Retirees of the union were invited to the DNC, and Harris is slated to hold a roundtable with the union ahead of Election Day, Axios reported. 

The DNC kicked off in Chicago on Monday, where the audience heard from a handful of high-profile Democrats, including Rep. Alexandria Ocasio-Cortez, former Secretary of State Hillary Clinton, and surprise remarks from Vice President Kamala Harris. 

As elected officials began filing into the convention center Monday, left-wing and anti-Israel protesters just blocks away from the United Center slammed the party for its support of Israel as the nation continues battling Hamas since October. The protesters demand the U.S. end funding to Israel, in addition as well as "Immigrant Rights and Legalization for All!" "Defend LGBTQIA+ & Reproductive Rights!" and "Stop police crimes! Community control of the police now!" according to the "March on the DNC 2024" website. 

Fox News Digital's Peter Aitken contributed to this report. 

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