Biden to join Harris on campaign trail for first time since dropping out of race

Joe Biden will join Kamala Harris on the campaign trail for the first time on Monday since standing aside six weeks ago to let the vice-president claim the presidential nomination following a poor debate performance.

The pair were due to appear together in Pittsburgh in the vital swing state of Pennsylvania at a Labour Day event aimed at cementing support from trade unions, a key Democrat constituency and a bedrock of Biden’s support as he has styled himself as “the most pro-union president in US history”.

Harris is expected to assume that mantle with a pledge to oppose the sale of US Steel – which is headquartered in Pittsburgh – to the Japanese company, Nippon. Biden has already voiced his opposition to the proposed sale.

Before her arrival in Pittsburgh, a Harris campaign official said she would “say that US Steel should remain domestically-owned and operated and stress her commitment to always have the backs of American steel workers.”

Harris’s commitment represents one of the few specific policy promises she has made since her ascent to top of the Democratic ticket following Biden’s 21 July announcement that he was abandoning his re-election bid.

Biden has since endorsed Harris and the pair appeared briefly together on stage at last month’s Democratic national convention in Chicago.

While the president has spent the last two weeks holidaying in California and at his home in Delaware, he is expected to campaign for Harris – focusing in swing states like Pennsylvania, Michigan and Wisconsin with a high concentration of white working-class voters whose allegiance may be crucial in November.

Harris has promised “a new way forward” while loyally adhering to the Biden’s policies, treading a thin line between distancing herself from his administration’s perceived economic failings – particularly on inflation – while tying herself to its success stories.

The emphasis on Monday appeared likely to mainly express her continued adherence to Biden, who became the first president to appear on a picket line last September when he joined striking car workers in Michigan, another crucial battleground state, in a show of support for the United Auo Workers (UAW) union.

Monday’s event is expected to be attended by local and national leaders of major unions including the International Brotherhood of Electrical Workers, the United Steelworkers and the AFL-CIO, the main US trade union body. Also expected were Bob Casey, the Democratic senator for Pennsylvania who is running for re-election, and the state’s governor, Josh Shapiro, who Harris considered as her running mate before eventually choosing Tim Walz.

Earlier, the vice-president visited Michigan – also a union stronghold – for an event in Detroit, where she was to be joined by the governor, Gretchen Whitmer, and two other union leaders, Shawn Fain of the UAW, and Randi Weingarten of the American Federation of Teachers.

Polls show Harris and Donald Trump running neck-and-neck in both Pennsylvania and Michigan, despite holding a small but consistent lead over the Republican nominee in national surveys. Both states are considered part of the Democrats’ “blue wall”, along with Wisconsin. It is the outcome in these states, plus a small number of other battleground states in the south and south-west, rather than the national vote total that is likely to determine the winner in November’s election under the US state-by-state electoral college system.

Trump has also pitched for union support and has sought the endorsement of the Teamsters union, whose head, Sean O’Brien, addressed July’s Republican national convention. However, JD Vance, Trump’s running mate, was booed last week when he spoke at a conference of the International Association of Firefighters and claimed to be part of “the most pro-worker Republican ticket in history”.