MILWAUKEE - Vice President Kamla Harris took the Democrats' convention on the road on Tuesday, as she and running mate Minnesota Gov. Tim Walz headed to nearby battleground Wisconsin.

Speaking in front of a packed Fiserv Forum, the same arena where the Republicans held their national nominating convention one month ago, Harris pointed to her battle against former President Trump, saying "this is not 2016 or 2020," and warning that "the stakes are higher."

Portions of the rally in Milwaukee, Wisconsin's largest city and a blue bastion in a crucial purple state, were beamed into the United Center 90 miles south in Chicago, site of the four-night Democratic National Convention.

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Democratic presidential nominee and U.S. Vice President Kamala Harris is shown on a screen as she speaks from a Milwaukee rally

Democratic presidential nominee Vice President Kamala Harris is shown on a screen as she speaks from a Milwaukee rally on Day 2 of the Democratic National Convention at the United Center in Chicago on Aug. 20, 2024. (REUTERS/Brendan Mcdermid)

The crowd of Democratic activists and supporters in Milwaukee - which the campaign put at over 15,000 - watched portions of the ceremonial nomination roll call from the convention in Chicago on the big screens inside the arena.

"The delegates at the Democratic National Convention, well they just completed their roll call. And they have nominated Coach Walz and me to be the next vice president and president of the United States of America," Harris said to sustained cheers as she came out on stage after the conclusion of the roll call.

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Since replacing President Biden at the top of the Democrats' 2024 ticket, 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.

U.S. Vice President and Democratic presidential candidate Kamala Harris and her running mate Minnesota Governor Tim Walz on stage at a campaign rally in Milwaukee

Vice President Kamala Harris and her running mate, Minnesota Governor Tim Walz, hold a campaign rally in Milwaukee on Aug. 20, 2024. (REUTERS/Kevin Lamarque)

Wisconsin is one of seven swing states that will likely determine the outcome of November's presidential election. Hours before Harris' arrival, Trump's running mate - Sen. JD Vance of Ohio - was campaigning in the southeastern corner of the state.

"Wisconsin, we have 77 days until the election. 77 days," Harris stressed. "And look, we know this is going to be a tight race until the very end. We have some hard work ahead of us. We have hard work ahead of us. But we like hard work."

It was Harris' third stop in Wisconsin since taking over for Biden in the 2024 showdown, and her second with Walz.

"The coach and I were together in Wisconsin just two weeks ago — the first rally after I announced he would be my running mate," Harris said. "And it is so good to be back with all of you."

She spoke from a stage in the middle of the arena, surrounded by the crowd, in a hall illuminated with flashing red, white and blue bracelets handed out by the campaign.

Harris and Walz on stage at a rally

Vice President Kamala Harris, the Democratic presidential nominee, and her running mate, Minnesota Gov. Tim Walz, headline a large rally at the Fiserv Forum in Milwaukee on Aug. 20, 2024. (Fox News - Paul Steinhauser)

Harris repeatedly criticized Trump, including over the issue of abortion, a leading issue that has energized Democrats since the overturning two years ago of the landmark Roe v. Wade Supreme Court ruling which legalized abortion.

"Just yesterday, when he was asked if he has any regrets about ending Roe v Wade, Donald Trump, without even a moment's hesitation, you would think you'd reflect on it for a second. Said no. No regrets," Harris said as she pointed to an interview by the former president.

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Walz, in energetic comments ahead of Harris' appearance, also took aim at Trump as he looked back at last month's GOP convention and the former president's nomination acceptance speech.

"Donald Trump subjected us to 92 minutes of ranting and raving insanity," Walz charged. "Now look, they left here riding high. They were feeling good. This thing was over. Well, trust me, Milwaukee, a hell of a lot can change in four weeks."

Walz, taking a verbal shot at the GOP ticket, argued that "you run a campaign based on fear like them, you're going to run into a little trouble when you run into a campaign that's based on joy."

The Trump campaign, criticizing Walz's energetic arrival on stage, wrote in a social media post that "you simply cannot trust a man who gesticulates this wildly. Freak!"

At one point during her speech, Harris reiterated her pledge to lower inflation, which has persistently plagued Americans during Biden's three and a half years in office.

"We believe in a future where we lower the cost of living! When I am president, I will bring down the cost of groceries," the vice president vowed.

The Trump campaign, in another social media post, spotlighted the clip and asked "Was there something stopping her from doing that in the 3.5 years she has been in the White House?"

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The rally by Harris and Walz came one night after the vice president made a little bit of political convention history, as she spoke from the podium at the United Center as she praised Biden.

The surprise appearance appeared to be a very rare occurrence of a presidential nominee speaking from the podium ahead of their formal acceptance speech, which is traditionally on the last night of a convention.

Biden, Jill Biden and Harris on DNC stage. Harris and Biden clasp hands

President Biden stands with Democratic presidential nominee Vice President Kamala Harris, left, and first lady Jill Biden during the first day of the Democratic National Convention on Monday, Aug. 19, 2024 in Chicago. (AP Photo/Jacquelyn Martin)

Biden's speech at the convention, which capped Monday night's session, 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.

Twenty-four hours later in Milwaukee, Harris pointed to her boss and asked "wasn't he terrific last night? And I know we are all deeply grateful for his lifetime of service to our nation. Thank you. Joe."

Her comments spurred chants of "thank you, Joe," throughout the arena."

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