Vice-President Kamala Harris will make the most important speech of her political life when she accepts the Democratic Party’s nomination for president a month after the party forced President Joe Biden to exit the race.On Wednesday, her energetic running mate Tim Walz formally accepted the party’s nomination, saying: “Kamala Harris is going to stand up and fight for your freedom to live the life that you want to lead.”Her own presidential ambitions were always clear, but had been undermined by her own shaky 2020 campaign and bumpy vice-presidential term.Since being thrust to the top of the ticket, she has tightened the race against Republican Donald Trump.Her forceful stump speeches have been met by a surge in enthusiasm from voters.If Harris wins on November 5, she will be the first black, South Asian woman elected president.In her speech Harris, 59, plans to talk about her life as the daughter of a Jamaican father and Indian mother and lay out her plans to tackle rising costs and advance personal freedoms, including abortion rights, aides said.They said she will also deliver a robust denunciation of former president Trump.“There is a guy who wants to divide us, and she will make the case that we simply cannot let that happen, that this is America and everybody can rise together,” Cedric Richmond, campaign co-chair and long-time adviser to Harris, told Reuters.Convention delegates got a preview on Monday, the convention’s first night, when Harris unexpectedly walked out on stage to the tune of Beyonce’s Freedom.“This November we will come together and declare with one voice as one people: We are moving forward,” she said.Whether Beyonce will appear on stage is a matter of speculation in convention hallways. The campaign declined to comment.“One of the things they teach us in law school is how to lay out your case,” said New York delegate Edwina Martin, a 60-year-old attorney. “That’s what (Harris) will be doing tomorrow.”“It’s going to blow the roof off,” added Amanda Taylor, a 47-year-old delegate from Missouri.Harris has raised a record-breaking $500mn in a month and has narrowed the gap or taken the lead against Trump in many opinion polls of battleground states.Yet while Democrats’ hopes are soaring and as Harris edges ahead in the polls, they know the battle is far from won.From Barack and Michelle Obama to Bill Clinton, senior figures have warned all week that Harris has a brutal fight on her hands to beat the 78-year-old Trump.Nationwide, she leads Trump 46.6% to 43.8%, according to a compilation of polls by FiveThirtyEight.However, the founder of the main outside spending group backing Harris’s campaign has warned that its private polling is less “rosy” than public polls suggest.US Representative Jim Clyburn, one of the earliest supporters of Harris at the top of the ticket, said the United States “has been in this moment before”.“It survived because enough people came together to continue our work to building a more perfect union and that is what she (Harris) is going to lay out,” said Clyburn, a powerful voice within the Democratic Party.Harris has yet to articulate much of her vision for the country, and Republicans say that Democrats have spent much of their time attacking Trump rather than explaining how they would govern.“In many ways this race has not yet even begun, but when it does, I hope, speaking not as a Republican but as an American, it’s about competing policy visions,” Vivek Ramaswamy, a former Republican presidential candidate, said at a news conference.Harris has spent weeks on the speech, making changes to drafts from lead speechwriter Adam Frankel, including during campaign trips on Air Force Two.Aides say she will discuss her plans to cut taxes for most Americans, boost the housing supply and ban “price gouging” by grocers.Her campaign has also proposed raising the corporate tax rate from 21% to 28%.The speech will include elements of foreign policy along with stories of women affected by abortion bans and other curbs on reproductive rights, the aides and advisers said.It will also include a nod to such traditional allies as labour unions and lean on Republican voices to persuade conservative voters to abandon Trump.Former US Representative Adam Kinzinger, one of the 10 House Republicans who voted to impeach then-President Trump, is one of several Republicans who are due to speak as well.Trump has spent the week campaigning in the handful of battleground states that will decide the election.He is due to visit the US-Mexico border in Arizona in the afternoon, where he will likely accuse Harris and her running mate Tim Walz of not doing enough to prevent illegal immigration.“If these two people take it over, this country is finished,” he said on Fox News on Thursday morning. “Open borders, no drilling, our country will die.”