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LONDON — One of U.K. Prime Minister Keir Starmer’s top advisers, Deborah Mattinson, will brief Kamala Harris’ presidential campaign on Labour’s election-winning strategy, POLITICO has learned.
In a sign of deepening ties between the two teams, Mattinson will travel to Washington D.C. next week where she will meet strategists from the Harris-Walz campaign and share insight on the center-left Starmer’s decisive path to victory in July’s U.K.’s election.
The polling veteran served as the then-opposition leader’s director of strategy for three years until the election, during which time she stressed the importance of winning back traditional Labour voters who had switched to the Tories under Boris Johnson.
Mattinson’s advice to the vice-president’s team was developed with the D.C.-based Progressive Policy Institute think tank, run by Starmer’s former director of policy Claire Ainsley.
One former colleague who worked alongside Mattinson on Labour’s campaign, granted anonymity to speak frankly, said she wanted to “put the ‘hope and change stuff’ to one side” and maintain a ruthless focus on Harris’s appeal in swing states.
Of seven states identified by the Harris and Trump campaigns as key electoral college battlegrounds, Harris leads Trump in three of them but only narrowly.
Mattinson is a fixture of the U.K. polling scene, known for her work with focus groups under former Labour prime ministers Tony Blair and Gordon Brown.
Her move comes after several of Starmer’s closest aides traveled to Chicago for the Democratic National Convention and met members of the vice president’s campaign team.
Labour’s election mastermind Morgan McSweeney and Downing Street communications director Matthew Doyle were among those who made the trip, alongside a select group of loyal new MPs.
Common challenges
The collaboration is just one strand in a growing transatlantic network of center-left think tanks and political operatives shaping policy and political messaging in Washington and London.
Common challenges on both sides of the Atlantic include immigration, housing and pressure from the left on issues such as the Gaza crisis.
Matthew McGregor, the former Labour digital director who also worked as a campaign strategist for former U.S. President Barack Obama, told POLITICO last month that collaboration between Labour and the Democrats had traditionally been “one-way traffic” — but that this is now changing.
For the first time in almost 25 years, McGregor said, the Democrats believe they have something to learn from Labour, after Starmer’s party returned to winning ways not seen since the era when U.K. PM Tony Blair and U.S. President Bill Clinton talked up a progressive center-left “third way.”
In particular there is interest Stateside in Labour’s journey since crashing to a heavy defeat in 2019 under previous leader Jeremy Corbyn, who is far left of center.
“Labour is one of the only Western parties that have recently won, or look likely to win, from the center left,” McGregor said.
“For Democrats following British politics, they have been intrigued by the speed [with] which Labour has gone from the Corbyn days to being in power now. It’s really got people’s attention.”
Jonathan Ashworth, director of the Labour Together think tank, was one of Labour’s senior figures in Chicago last month for the DNC, and served as a key strategist in the party’s successful summer campaign to oust the Tories after 14 years in power.
He said Democratic operatives were “interested in how we made the arguments [on border security], because they intend to make the same arguments as well.”
“We kept reminding people that he was a hard guy who put people behind bars and foiled terrorist plots,” Ashworth said of Starmer, who — like Harris — is a former prosecutor.
“[Harris], like Keir, is relentlessly pushing this message that she’s a prosecutor who has put criminals behind bars.”
