"America has tried these failed promises before, but we are not going back."
Harris also said they planned to ban assault rifles and introduce a swathe of the new gun laws.
She also said they would stop and reverse all "extreme abortion laws".
"When Congress passes a law to restore reproductive freedoms, as President I will sign it into law."
"We have an election to win... are you ready to get to work?"
"Let's make no mistake, this campaign is just not just about us versus Donald Trump, this is about who we fight for."
Harris spoke of election promises, such as affordable health and dignified retirement.
"Building up the middle class will be a feature of my presidency, when the middle class is strong, America is strong."
When speaking of Project 2025 she said: "Can you believe they put that thing in writing?"
She spoke about her time as a court room prosecutor before she was elected on the US senate.
"I took on perpetrators of all kinds, predators who abused women, fraudsters who ripped off consumers, cheaters who broke the rules for their own gain, so here me when I say, I know Donald Trump's type."
"I will proudly put my record against him any day of the week."
She was met with loud cheers as she said she had enough votes for the democratic nomination.
"Friends we have 105 days until election day, and in that time we have some work to do, but we are not afraid of hard work, are we?"
"In 2024 we will win again," Harris said.
She spoke about the "incredible" President Joe Biden. "It has truly been one the greatest honours of my life to support President Joe Biden".
She said his legacy was "unmatched in modern history".
"I know we are all deeply grateful for his continuous serving to our nation."
Vice President Harris started her address to a roaring crowd who chanted her name.
She said she was "glad to be back in Wisconsin" among the leaders and thanked the teacher who introduced her.
Kamala Harris is speaking in Milwaukee, Wisconsin. This is her first campaign rally since Joe Biden announced he wouldn't run as the Democrat's nominee.