Tim Walz never attended an Ivy League school. He never wrote a political memoir. He once worked at a tanning bed factory in Jonesboro, Ark. And until he was 40, he never showed much interest in a career in politics.

Mr. Walz, the 60-year-old governor of Minnesota chosen by Vice President Kamala Harris as her running mate on Tuesday, had not devoted his life to reaching this pinnacle.

In selecting Mr. Walz, Ms. Harris has picked a one-man rejoinder to the idea that the Democrats are the party of the cultural and coastal elite. His biography and his style are a sharp contrast not only to Ms. Harris, who is from California, but also to former President Donald J. Trump, a New York billionaire, and to some degree to Mr. Trump’s running mate, JD Vance, who graduated from Yale Law School (and wrote a best-selling memoir).

Mr. Walz has led a life that stands out in the top echelon of American politics: a tableau filled with scenes of farming, turkey hunting, weekends of National Guard duty, public schools and coaching the local high school football team to a state championship.

Since turning to politics, Mr. Walz has used this biography to his political advantage and it was no small part of what drew Ms. Harris to Mr. Walz, who until weeks ago was virtually unknown to most Democrats. With his broad smile and unpolished style, it was the Minnesota governor — more than any other Democrat — who was able to conceive and deliver Democrats’ new favorite attack on Mr. Trump and his party: that they are “creepy” and “weird as hell.”

For all his affability, Mr. Walz has displayed, at times, shrewd political instincts. His positions have evolved as his ambitions have broadened. He has capitalized on key moments. After the Democrats won control of both houses of the State Legislature in 2022, he enacted a raft of liberal legislation — policies that are far more popular in cities and suburbs than in the rural, working-class communities that raised him.

“He ran on a ticket of ‘One Minnesota’: Let’s pull everybody together and unify everyone,” said Representative Lisa Demuth, a Republican and the minority leader in the Minnesota House, who represents a largely rural area outside the Twin Cities. “That is absolutely not what we have seen.”

Still, over the course of his life, much of it spent in conservative corners of Nebraska and Minnesota, Mr. Walz has effectively used his normalcy to connect. Even Republicans who said they would never vote for him, particularly as the running mate of Ms. Harris, described him as self-effacing and familiar.

Although he spent more than a decade in Congress and another five years in the governor’s mansion, the reaction among friends and neighbors to the news of his ascent on Tuesday was not knowing expectation, but pleasant surprise.

“He is genuine, he’s a ball of energy,” said Sherri Blasing, who used to live near Mr. Walz in Mankato, Minn.

“It’s not every day that your neighbor becomes a vice-presidential candidate,” she added. “You can’t go two steps down the sidewalk without someone saying, ‘Can you believe this?’”

A Nebraska Boyhood

Mr. Walz was born in West Point, Neb. (population: 3,500), and raised in Butte (population: 285), a town planted among the cornfields and the rolling hills of one of the most rural areas of one of the nation’s most rural states.

As a teenager, Mr. Walz spent summers working on a family farm, and he has said that his high school graduating class included 25 students, 12 of whom were cousins. That, he would joke years later, made finding someone to date “kind of a problem.”

He was raised Catholic, by a father who was a school administrator and a mother who was a homemaker. (He became Lutheran after getting married, but does not draw much attention to his faith.)

Mr. Walz grew up hunting — bringing his rifle to school so he could shoot turkeys with friends after football practice. He enlisted in the National Guard at 17, following in the footsteps of his father, who served in the Army during the Korean War.

His father died of lung cancer when he was 19. In 1989, Mr. Walz earned a bachelor’s degree from Chadron State College in Nebraska and went to China for a year to teach English and American history.

He returned home to Nebraska; taught global geography; met his wife, Gwen, a fellow teacher; and began coaching. In September 1995, at 31, Mr. Walz was pulled over by a Nebraska state trooper for driving at 96 miles per hour on a road where the speed limit was 55 m.p.h. Mr. Walz failed a field sobriety test and ultimately pleaded guilty to reckless driving. Mr. Walz told his principal and offered to resign, his lawyer said at the time, but he kept his job and stopped drinking.

The next year, the couple moved to Mankato, a small city surrounded by farming communities in southern Minnesota. Mr. Walz kept teaching and coaching, growing into the sort of coach who started practice by telling preteens, “You’re the greatest seventh-grade basketball team ever!” said Ben Ingman, who was coached by Mr. Walz.

Mr. Ingman once watched Mr. Walz teach his son, Gus, to ride a bike. “When Gus finally got it, he exploded, just with his hands over head, yelling, over the moon,” he said.

Mr. Walz led school trips to China and helped turn around a struggling Mankato West High School football team. He and his wife created the first gay-straight alliance group on campus after a senior, Jacob Reitan, came out as gay in the late 1990s.

Classmates taunted him, Mr. Reitan, 42, recalled in an interview. Someone smashed his car window, and he came home one day to find a slur etched on his driveway with chalk. As scary as coming out was, Mr. Reitan said, “it was made a hell of a lot easier because of Tim and Gwen Walz,” he said.

Mr. Walz has said he understood how his support for the club carried weight.

“You have an older, white, straight, married, male football coach who’s deeply concerned that these students are treated fairly and that there is no bullying,” he said in a 2018 campaign ad.

‘Who Is This Guy?’

Mr. Walz’s career in politics began because of President George W. Bush. In the governor’s telling, he had tried to escort a group of high school students to a rally for Mr. Bush in Mankato, in 2004, but they were turned away because one student had a sticker supporting Mr. Bush’s opponent, John F. Kerry, the Democratic senator from Massachusetts.

Mr. Walz was incensed. Within days, he said, he signed up to volunteer for the Kerry campaign, finding common cause with a fellow veteran opposed to the war in Iraq.

The tense confrontation at the rally was a “sad epiphany moment,” he later said, and it set in motion a long-shot campaign against a six-term Republican incumbent in their largely rural, conservative Minnesota district in 2006.

Mr. Walz’s former students at Mankato West High School signed up to knock on doors, even though it seemed nearly inconceivable that this first-time Democratic candidate without a donor base or name recognition could win in a red district against an entrenched incumbent.

“This is farm country, it’s very conservative,” said Nicole Griensewic, 41, who was in Mr. Walz’s global geography class and volunteered for the campaign. “It had been known as a Republican district for so long, so it was like, Who is this guy?”

Mr. Walz was trained in campaigning that year at Camp Wellstone, a weekend workshop named after Paul Wellstone, a onetime senator of Minnesota whose staunch liberal politics and unflashy style are a model for many Democrats in the state.

Mr. Walz arrived wearing bluejeans, a T-shirt and sneakers — hardly the wardrobe of a polished candidate, said Peggy Flanagan, then a Minneapolis School Board member who was assigned to mentor him that weekend.

“He walked in and was like, ‘I’m Tim Walz and I want to run for Congress,’ and we were like, ‘As a Democrat?’” recalled Ms. Flanagan.

Mr. Walz rode to victory with his army of student volunteers and a strong debate performance, and the widespread dissatisfaction with the Bush administration that year helped Democrats take control of the House of Representatives.

‘He Did His Work.’

On Capitol Hill, Mr. Walz, who served 24 years in the National Guard, emerged as a vocal critic of the Iraq war. He became influential on agriculture and veterans issues. But he was by most measures a low-profile member of Congress, a go-along, get-along backbencher who tended to follow the Democratic line in his votes.

“He’s never been a show horse,” said Blois Olson, a Minnesota political analyst. “He did his work. I think that’s how many rank-and-file members are on both sides.”

He supported Obamacare and an increase in the minimum wage, and pushed for expanding education benefits for veterans of the wars in Iraq and Afghanistan. He took a particular interest in issues of importance to his district: agriculture and veteran issues. And the former teacher who had supported gay students in Minnesota was among the most vocal supporters of repealing the military policy that barred openly gay people from serving in uniform.

Patrick Murphy, a former Democratic congressman from Pennsylvania, called Mr. Walz “someone you just want to be around.” Among those expressing pleasure at Ms. Harris’s decision to pick Mr. Walz was Nancy Pelosi, the former House Democratic leader, who served with Mr. Walz in Congress.

After several successful re-election campaigns, warning signs arrived for Mr. Walz. Rural Democrats were an endangered species. In 2016, voters in his district were becoming enamored with Mr. Trump. Mr. Walz squeaked to a sixth term with just 50.4 percent of the vote that year, defeating his Republican opponent, Jim Hagedorn, by less than one point. It was his smallest victory margin in all his runs for Congress.

In March of 2017, Mr. Walz announced he was leaving Congress to run for governor of Minnesota. “He probably would have lost the seat if had run again in ’18 — which is one of the reasons he ran for governor,” said Mr. Olson.

‘One Minnesota’

In 2018, he was elected as governor with his one-time political mentor, Ms. Flanagan, as his lieutenant governor. They campaigned under the slogan “One Minnesota,” presenting themselves as unifying leaders in a polarizing time.

Perhaps the biggest crisis they faced was the mayhem and the violence ignited by the police killing of George Floyd in Minneapolis in May 2020. A wave of protests, looting and arson spread through Minneapolis in the days that followed, prompting the city’s mayor to ask the governor to deploy National Guard soldiers.

Mr. Walz didn’t immediately heed that request, which led critics to call him indecisive in a moment of peril. Hundreds of businesses were looted and set on fire that week, resulting in an estimated $500 million worth of damage. The governor, who ultimately sent troops under his command to Minneapolis, has defended his response, arguing that elected officials did their best in the face of monumental challenges.

“I simply believe that we try to do the best we can,” he said recently at a news conference.

When he campaigned for re-election in 2022, rivals sought to misleadingly tie him to the movement to defund the police and criticized him over his lockdown policies during the Covid-19 pandemic.

Mr. Walz lost ground with his old constituents between his first and second governor races. In 2018, he won more than 49 percent of the vote in his old congressional district, slightly more than his Republican opponent. When he sought re-election four years later, he lost that congressional district by more than seven percentage points.

But he won — and Democrats seized full control of the State Legislature, lifted, in no small part, by the strong turnout by liberal voters upset over the Supreme Court’s decision that ended the federal right to abortion.

With a one-seat majority in the State Senate, Mr. Walz signed into law bills that codified the right to abortion under state statute, legalized recreational marijuana, funded free meals for all school children, required employers to provide paid medical and family leave and tightened gun restrictions.

Mr. Walz’s allies and critics took notice when he began accepting invitations to appear on television news programs this summer, casting himself as a more authentic embodiment of small-town values than Mr. Vance. He argued that Democrats should focus less on talking about the perils of a second Trump term and more on sharing an upbeat vision described in plain terms.

The energy was familiar to his former students, neighbors and constituents watching at home.

“When I hear him talking, his cadence and the way that he presents, and his speech is exactly the same as it was in high school,” said Ms. Griensewic, his former student.