Tim Walz has formally accepted his nomination to be the Democratic vice presidential candidate in November’s US election, rallying the party faithful in Chicago with a message of freedom and hope.

“It’s the honour of my life to accept your nomination for vice president of the United States,” Walz said on Wednesday, as he took to the stage at the end of the third day of the Democratic National Convention. “What all we’re all here tonight for one beautiful, simple reason. We love this country.”

Walz, the 60-year-old governor of Minnesota, was a relative unknown until Kamala Harris picked him as her running mate just over two weeks ago.

Walz talked of his upbringing in a town of just 400 people in Nebraska, his service with the National Guard and his experience as a teacher.

He stressed the importance of preserving personal freedoms, taking a swipe at Republicans who have rolled back abortion rights, adding that in his experience most Americans considered such issues to be private matters.

“We respect our neighbours and the personal choices that they make,” he said of his Midwestern community. “And even if we would not make those choices for ourselves, we have one rule: ‘Mind your own damn business.’”

The crowd, many holding “Coach Walz” banners in reference to his years coaching football, cheered and waved.

Freedom was the theme of the third day of the convention with Democratic luminaries such as former President Bill Clinton taking the stage, as well as celebrities from singers Stevie Wonder to John Legend to comedian Mindy Kaling and media personality Oprah Winfrey.

‘Decency and respect’

While the message was overwhelmingly one of optimism as the speakers endorsed Harris and Walz, there were also plenty of swipes at Trump who was portrayed as vain and self-obsessed.

“Next time you hear him, don’t count the lies. Count the I’s,” the now 78-year-old Clinton told the crowd.

There were deafening cheers as Winfrey, who later described herself as an independent, walked onto the stage.

She rallied the crowd with a powerful endorsement of democracy and the need to get out the vote.

“I’m calling on all you independents and all you undecideds,” Winfrey said. “Values and character matter in leadership and in life. Decency and respect are on the ballot in 2024.”

Harris emerged as the Democrats’ candidate last month after President Joe Biden stepped aside.

The convention has also featured a number of Republicans who have turned against Trump, who was president from 2017 to 2021.

On Wednesday, the Democrats put the spotlight on January 6, 2021, with a video that showed Trump calling on supporters to be strong and fight before they stormed the US Capitol to try and block Biden’s 2020 victory.

The delegates sat in stunned silence, a sharp contrast to their roars and applause throughout the night.

Olivia Troye, who quit her White House national security job under Trump after the Capitol assault, said the Republican candidate was laying the groundwork to undermine the 2024 election.

Geoff Duncan, the former lieutenant governor of Georgia, spoke directly to the camera to tell fellow Republicans watching from home that they needed to “dump Trump”.

“If you vote for Kamala Harris in 2024, you’re not a Democrat. You’re a patriot,” he said.

Democrat Nancy Pelosi, who was House speaker at the time of the Capitol assault, said: “Let us not forget who assaulted democracy on January 6: He did. But let us not forget who saved democracy that day: We did.”

Harris, 59, is due to formally accept her nomination on Thursday when she will speak to the convention on its final night.