Liz Truss — a tax-cutting crusader who has modeled herself on Margaret Thatcher and endeared herself to the Conservative Party’s pro-Brexit right wing — has won its leadership election and will take over from Boris Johnson tomorrow as the UK’s new leader.

Truss, who has served as Boris Johnson’s foreign secretary for the past year, won 57% of the votes of Conservative Party members to become its leader. Rishi Sunak took 43%.

It was a closer than anticipated victory for the longtime favorite, who was popular among party members but won the support of less than a third of her MPs earlier in the leadership contest.

She began her victory speech by congratulating her opponent, Rishi Sunak, who pushed her closer than many expected in the final ballot.

She then gave a hearty tribute to Boris Johnson, who she will replace as prime minister on Tuesday after months of scandals forced him to resign.

“Boris: you got Brexit done, you crushed Jeremy Corbyn, you rolled out the vaccine, and you stood up to Vladimir Putin,” Truss said. “You are admired from Kyiv to Carlisle.”

“I know that our beliefs resonate with the British people,” she told the crowd of Conservative members. “I campaigned as a Conservative and I will govern as a Conservative.”

The incoming UK prime minister has promised a “bold plan” to cut taxes and said she will address spiraling energy prices that are driving a cost-of-living crisis in the country.

But Liz Truss offered no details of what either plan will involve; throughout her campaign, her critics, including opponent Rishi Sunak, have pushed her to detail her next steps, with households facing another spike in costs next month.

“I will deliver a bold plan to cut taxes and grow our economy,” Truss said. “I will deliver on the energy crisis, dealing with people’s energy bills.”