Democratic presidential candidate Kamala Harris selected Minnesota Governor Tim Walz to be her running mate on Tuesday, choosing a progressive policy champion and a plain speaker from America’s heartland to help win over rural, white voters, according to sources familiar with the matter.

Campaign officials did not respond to requests for comment. An official announcement was expected on Tuesday morning.

Walz, a 60-year-old US Army National Guard veteran and former teacher, was elected to a Republican-leaning district in the US House of Representatives in 2006 and served 12 years before being elected governor of Minnesota in 2018.

As governor, Walz has pushed a progressive agenda that includes free school meals, goals for tackling climate change, tax cuts for the middle class and expanded paid leave for Minnesota workers.

Walz has long advocated for women’s reproductive rights but also displayed a conservative bent while representing a rural district in the US House, defending agricultural interests and backing gun rights.

Harris, the daughter of immigrants from Jamaica and India, is adding a popular Midwestern politician whose home state votes reliably for Democrats in presidential elections but is close to Wisconsin and Michigan, two crucial battlegrounds.

Such states are seen as crucial in deciding the November 5 election, and Walz is widely seen as skilled at connecting with white, rural voters who in recent years have voted broadly for the Republican Donald Trump, Harris’ rival for the White House.

Harris chose Walz over Josh Shapiro, the governor of Pennsylvania, who had been seen as essential to delivering his crucial battleground state.

Harris became the Democratic Party’s standard bearer after President Joe Biden ended his re-election campaign last month. Since then, she has raised hundreds of millions of dollars and recast the race against Republican Donald Trump with a boost of energy from her party’s base.

Harris was expected to appear with her running mate at an event in Philadelphia on Tuesday evening.

The Harris campaign hopes Walz’s extensive National Guard career, coupled with a successful run as a high school football coach, and his Dad joke videos, opens new tab will attract such voters who are not yet dedicated to a second Trump term in the White House.

Harris, 59, has revived the Democratic Party’s hopes of an election victory since becoming its candidate after President Joe Biden, 81, ended his failing reelection bid under party pressure on July 21.

Walz was a relative unknown nationally until the Harris “veepstakes” heated up, but his profile has since surged. A popular member of Congress, he reportedly had the backing of powerful former House Speaker Nancy Pelosi, who was instrumental in persuading Biden to leave the race.

Harris and Walz will face Trump and his running mate JD Vance, also a military veteran from the Midwest, in the November election.

Stumping for Harris, sometimes in a camouflage baseball hat and T-shirt, Walz has attacked Trump and Vance as “weird,” a catchy insult that has been picked up by the Harris campaign, social media and Democratic activists.