Kamala Harris picked Minnesota Gov. Tim Walz to be her running mate on Tuesday, giving the vice president a popular figure in Midwest politics and an effective communicator on the Democratic ticket as she looks to defeat former President Donald Trump in November.

Walz, 60, who was elected governor of Minnesota in 2018, has been touted by Democrats as an effective communicator for the party. He has been widely credited with starting the messaging strategy that has taken off within the Harris campaign of branding Trump and his running mate, Ohio Sen. JD Vance, as “weird.” 

"One of the things that stood out to me about Tim is how his convictions on fighting for middle class families run deep. It’s personal," Harris wrote in a post on Instagram. "He grew up in a small town in Nebraska, spending summers working on his family’s farm. His father died of cancer when he was 19, and his family relied on Social Security survivor benefit checks to make ends meet. At 17, he enlisted in the National Guard, serving for 24 years. He used his GI Bill benefits to go to college, and become a teacher. He served as both the football coach and the advisor of the Gay-Straight Alliance."

Harris went on to say that Walz's background "informs his record," hailing his bipartisan work on infrastructure investments in the state, as well as his efforts cutting taxes for working families and passage of law guaranteeing paid family and medical leave.

"He made Minnesota the first state in the country to pass a law providing constitutional abortion protections after the Supreme Court overturned Roe v. Wade, and as an avid hunter, he passed a bill requiring universal background checks for gun purchases," she added. "But what impressed me most about Tim is his deep commitment to his family: Gwen, Gus, and Hope. Doug and I look forward to working with him and Gwen to build an administration that reflects our shared values."

Walz called it the "honor of a lifetime" in a post of his own on social media.

"I’m all in. Vice President Harris is showing us the politics of what’s possible. It reminds me a bit of the first day of school," said Walz, a former educator. "So, let’s get this done, folks!"

The two are set to make their first joint appearance at a rally in Philadelphia later Tuesday.

The decision caps a hectic period in American politics that began with President Joe Biden’s decision to step aside from the Democratic ticket last month and endorse Harris to take his place – and the groundswell of support in the days that followed. 

Biden himself praised the pick, hailing his record over a nearly two decade-long working relationship.

"A husband and father, he's been a school teacher and a high school football coach," the president said. "He served for 24 years in the Army National Guard and became the highest ranking enlisted soldier to ever serve in Congress. As Governor, he's been a strong, principled, and effective leader."

"The Harris-Walz ticket will be a powerful voice for working people and America's great middle class," Biden added. "They will be the strongest defenders of our personal freedoms and our democracy. And they will ensure that America continues to lead the world and play its role as the indispensable nation. It's time for all Democrats—and indeed all Americans—committed to freedom, democracy, and American leadership in the world to rally behind the Harris-Walz ticket. Every generation of Americans faces a moment where they are asked to defend American democracy. That moment is now."

Harris' pick of Walz could also effectively snuff out Trump's hopes of flipping Minnesota, a state the ex-president has targeted extensively despite the fact that it hasn't picked a Republican for president since 1972.

Minnesota has previously produced two vice presidents: Hubert Humphrey, who served under Lyndon Johnson, and Walter Mondale, who served under Jimmy Carter and ran for president in 1980 against Ronald Reagan.

Shortly after Harris' announcement, a slew of running mate hopefuls announced their support for Walz.

"As I’ve said repeatedly over the past several weeks, the running mate decision was a deeply personal decision for the Vice President – and it was also a deeply personal decision for me. Pennsylvanians elected me to a four-year term as their Governor, and my work here is far from finished – there is a lot more stuff I want to get done for the good people of this Commonwealth," Pennsylvania Gov. Josh Shapiro said in a statement, adding: "Vice President Kamala Harris has my enthusiastic support – and I know that Governor Tim Walz is an exceptionally strong addition to the ticket who will help Kamala move our country forward. Lori and I consider Tim and Gwen to be good friends of ours and we are excited for them and for the country to get to know the great people we know them to be."

"Vice President @KamalaHarris and Governor @Tim_Walz are going to move us forward," Arizona Sen. Mark Kelly wrote on social media. "They’re already building a campaign to unite our country — and @GabbyGiffords and I are ready to do everything we can to help them win."

"Tim Walz is an exceptionally effective governor - and also great to work with," Transportation Secretary Pete Buttigieg said. "I’m excited for what his Midwestern voice, military experience, and common-sense values will bring to our winning ticket, and for everything the Harris-Walz administration will deliver for Americans."

North Carolina Gov. Roy Cooper, a longtime friend of Harris' who removed himself from consideration over concerns about his Republican lieutenant governor assuming power with him out of state campaigning, called the choice of Walz "outstanding."

"Governors like him know how to get the job done, and he will be an outstanding vice president, doubling down on his work to support middle class families, protect reproductive freedom and safeguard our democracy" said Cooper in a statement posted to social media. 

The pick of Walz also drew rave reviews from former President Barack Obama and former first lady Michelle Obama.

"When a presidential candidate chooses a running mate, it says a lot about who they are and what kind of president they’ll be," the Obamas said in a statement, adding: "By selecting Tim Walz to be her vice president from a pool of outstanding Democrats, Kamala Harris has chosen an ideal partner – and made it clear exactly what she stands for."

"Governor Walz doesn’t just have the experience to be vice president, he has the values and the integrity to make us proud," the Obamas continued. "As governor, Tim helped families and businesses recover from the pandemic, established paid family leave, guaranteed the right to an abortion, and put common sense gun safety measures in place to keep communities safe. But Tim’s signature is his ability to talk like a human being and treat everyone with decency and respect – not all that surprising considering the fact that he served in the National Guard for 24 years and worked as a high school social studies teacher and football coach before being elected to Congress."

"Like Vice President Harris, Governor Walz believes that government works to serve us," they added. "Not just some of us, but all of us. That’s what makes him an outstanding governor, and that’s what will make him an even better vice president, ready on day one. Michelle and I couldn’t be happier for Tim and Gwen, their family, and our country."

Other Democrats, particularly progressives, celebrated Harris' pick.

"Vice President Harris made an excellent decision in Gov. Walz as her running mate," said New York Rep. Alexandria Ocasio-Cortez, a prominent progressive, in a post on social media. "Together, they will govern effectively, inclusively, and boldly for the American people. They won’t back down under tight odds, either - from healthcare to school lunch."

"Our North Star state Governor has signed universal school meals, paid family and sick leave, marijuana legalization, and protections for reproductive rights into law," Minnesota Rep. Ilhan Omar wrote on social media in a note of congratulations, adding: "Bringing Minnesota nice to the ticket."

Republicans quickly began attacking Walz's progressive bonafides, with Trump's campaign press secretary calling him a "dangerously liberal extremist" and his Super PAC, Maga Inc., sending a press release with a headline reading: "Tim Walz is an incompetent liberal."

Vance, for his part, told reporters Tuesday that he called Walz to congratulate him.

"I actually called Tim Walz, I left a voicemail, I didn’t get him," the Ohio lawmaker said, recounting the message: "I just said, ‘Look, congratulations. Look forward to a verbose conversation. And enjoy the ride.’ And maybe he’ll call me back, maybe he won’t.”

Vance, who is having an event in Philadelphia the same day as Harris and Walz, said the running mate pick "just highlights how radical" the vice president is, and said they "make an interesting tag team."

In a statement, Republican National Committee Chair Michael Whatley called Harris and Walz "the most radical, far-left ticket in the history of our country," adding, "In 2020, Walz let rioters burn the Twin Cities — then Kamala stepped in to fundraise for their bail and get them back on the streets. This ticket puts criminals ahead of citizens. Donald Trump will put America first."

Walz, a former public school teacher and military veteran, also serves as a co-chair of the DNC Rules Committee and the chair of the Democratic Governors Association. He previously served in the House of Representatives representing a district that had leaned Republican. 

But Walz does not hail from what is considered to be a major battleground state and has a record that some consider more progressive and therefore potentially less enticing to swing voters. 

First elected governor in 2018, Walz worked effectively with a split legislature for his first year in office, but that spirit of bipartisanship turned sour amid the COVID-19 pandemic in 2020. Walz relied on emergency powers to lead the state’s response. Republicans chafed under restrictions that included lockdowns, closing schools and shuttering businesses. They retaliated by firing or forcing out some of his agency heads. But Minnesotans who were stuck at home also got to know Walz better through his frequent afternoon briefings in the early days of the crisis, which were broadcast and streamed statewide.

Walz won reelection in 2022 by nearly 8 points over his GOP challenger, Dr. Scott Jensen, a physician and vaccine skeptic. Democrats also kept control of the House and flipped the Senate to win the “trifecta” of full control of both chambers and the governor’s office for the first time in eight years. A big reason was the Supreme Court’s Dobbs decision, which held that the Constitution doesn’t include a right to abortion. That hurt Minnesota Republicans, especially among suburban women.

Walz and other Democrats went into the 2023 legislative session with an ambitious agenda — and a whopping $17.6 billion budget surplus to help fund it. Their proudest accomplishments included sweeping protections for abortion rights that included the elimination of nearly all restrictions Republicans had enacted in prior years, including a 24-hour waiting period and parental consent requirements. They also enacted new protections for trans rights, making the state a refuge for families coming from out of state for treatment for trans children.

Their other major accomplishments included tax credits for families with children that were aimed at slashing childhood poverty, as well as universal free school breakfasts and lunches for all students, regardless of family income. They also enacted a paid family and medical leave program, legalized recreational marijuana for adults and made it easier to vote.

Republicans still criticize Walz for his response to the sometimes violent unrest that followed the murder of George Floyd by a Minneapolis police officer in 2020, which included the torching of a police station.

Since the vice president announced she would seek the nomination, Harris has been swamped with support from the party’s biggest names – from former presidents like Barack Obama and Bill Clinton to party leaders like former House Speaker Nancy Pelosi, Senate Majority Leader Chuck Schumer and House Democratic Leader Hakeem Jeffries – as well as record-setting fundraising, notching $310 million in July. 

She's also virtually erased Trump's leads in polling in both nationwide and state-level polls in must-win battlegrounds, closing the gap with the Republican former president and, in some surveys, overtaking him.

Harris’ announcement comes the day after the Democratic National Committee’s roll call vote closed, allowing her to formally clinch the party’s presidential nomination. She’s the first woman of color to lead a major political party's ticket. If elected, she would become the first woman, Black woman and person of South Asian descent to become president. 

The Associated Press contributed to this report.