Kamala Harris introduced her running mate, Tim Walz as “the kind of vice-president America deserves,” at a raucous rally in Philadelphia that showcased Democratic unity and enthusiasm for the party’s Democratic presidential ticket ahead of the November election. Casting their campaign as a “fight for the future”, Harris and Walz were repeatedly interrupted by applause and cheering as they addressed thousands of battleground-state voters wearing bracelets that twinkled red white and blue at Temple University’s Liacouras Center – a crowd her team said was its largest to date. “Thank you for bringing back the joy,” a beaming Walz said to Harris, after she presented him to the crowd, reciting his biography as a teacher, high school football coach, military veteran, legislator and governor.

Harris, who has served as vice-president to Joe Biden for three and a half years, said Walz, the Minnesota governor, would be “ready on day one”, and said the race between them and the Republican presidential ticket of Donald Trump and JD Vance was a “matchup between the varsity team and the JV squad”. Harris announced Walz as her running mate on Tuesday morning, hours after she formally secured the Democratic nomination becoming the first woman of color to lead a major party ticket. With the governor’s selection, Democrats capped one of the wildest periods in American political life that led Biden to abandon his re-election bid and endorse his vice president last mo.