Most of the commentary in the presidential primaries has been focused on whether candidates are “too far left” or “too centrist” to be electable.

But research, and our experience, suggests whether a candidate can connect on a deeper level with voters’ fundamental values shapes how their policies and ideology is seen by voters as much as the issues they prioritize or the positions they take.

This reality presents a major challenge for progressives, who find themselves trapped in a box. Many progressives have grown uncomfortable talking about basic values because too often conservative pundits have tainted them with mean-spirited twists. Conservative politicians have invoked “faith” as a reason to restrict the rights of women or gay people, “family” in a way that disparages single mothers, and “patriotism” as a cudgel against those who question wrong-headed wars. So, too, politicians have employed “law and order” to evoke fear of black people, and valuing “hard work” as code for adopting overly punitive approaches to people down on their luck.

But ceding these values is a big mistake because it cuts off progressives from what matters most to people. When Americans are asked what gives them a sense of meaning in life, family is the number-one answer by a wide margin. Today, 71 percent of Americans still report praying at least weekly. Likewise, more than three in five Americans believe the United States has a special role in human history, and most people of all racial backgrounds want to live in neighborhoods that are safe, and believe fiercely in the dignity of work.

Progressives operating outside these mainstream values risk finding themselves outside of what is common sense for most Americans, which could weaken the public’s foundation of trust in progressives, regardless of their policy proposals.

Progressives seeking to recapture mainstream values for themselves can learn a lot about how to do so from a political figure who did it better than most: Robert F. Kennedy (RFK). When he ran for president in 1968, working-class white and black voters were at each other’s throats as riots raged across American cities. And yet RFK was able to simultaneously win the enthusiastic support of black and Hispanic voters and working-class whites, some of whom had supported Alabama’s segregationist governor George Wallace for president.

Kennedy had crosscutting appeal in part because he championed seven values that Americans cherish. Although the world has changed a great deal since 1968, evidence from polls, and our direct experience working with leading organizations on the ground, suggests that these basic values still animate millions of Americans, across racial lines. Some of the 2020 presidential candidates do a good job of invoking individual values, but none embrace them all the way Kennedy did.

1. He punched up, but never down

Though born to great wealth, RFK managed to convey a populist sensibility. Culturally, “Robert Kennedy had ‘cop’ written all over his public image,” Ted Sorensen wrote. He was the politician most disliked by big business because he went after wealthy individuals by name for failing to pay much in the way of taxes. Kennedy was quick to denounce racism where he saw it—but if he employed “deplorable,” it was as an adjective to describe statements or actions, not as a noun to identify a group of people. RFK would drive around less advantaged neighborhoods with his children and tell them: “Remember, you are more fortunate and lucky, but you are not better than them.” Today, Senator Bernie Sanders punches up consistently at the “billionaire class” and has resisted punching down at working-class people, whom he champions across racial lines.

2. He represented the importance of family.

Everyone in the country knew that RFK cherished his family. The extended Kennedy family football games were the stuff of legend. “The Kennedy family” was a well-known phrase in a way that “the Reagan family” or “the Nixon family” were not. RFK was enormously devoted to his own children, and campaign ads reminded voters of this commitment.

Today, progressives should proudly champion family—in all its modern forms—as a central reason to support liberal policies. One reason to be for marriage equality, or paid family leave policies, is precisely that family can give enormous meaning and stability in people’s lives. Union workers often say they support their union not so much for ideological reasons, such as demanding “economic justice,” but rather because the union helps members provide for their families and have more time with them on weekends and vacation. Today, former vice president Joe Biden speaks of his days commuting home from the Senate every night to Delaware after his first wife died, noting, “By focusing on my sons, I found my redemption.”

Without a full-throated embrace of family, progressives can sound disconnected from the very thing that millions of Americans sacrifice for every day.

3. He emphasized the patriotic duty of Americans.

RFK opposed the Vietnam War as wrongheaded and immoral, but people also knew that he believed strongly in the duty of Americans to defend national interests and American ideals. He served in the military himself, and his brother, of course, famously said, “Ask not what your country can do for you—ask what you can do for your country.” In the same vein, RFK told Notre Dame students that he opposed draft deferments for those in college: “You’re getting the unfair advantage while poor people are being drafted,” he said.

Today, there are ways to embrace patriotism in new ways. Senator Elizabeth Warren, for example, has called for greater “economic patriotism” among corporations. She writes that many companies “show only one real loyalty: to the short-term interests of their shareholders, a third of whom are foreign investors. If they can close up an American factory and ship jobs overseas to save a nickel, that’s exactly what they will do—abandoning loyal American workers and hollowing out American cities along the way.”

4. He signaled a respect for people’s religious faith.

Everyone knew RFK was a devout Roman Catholic. Jaqueline Kennedy is said to have quipped, “I think it’s so unfair of people to be against Jack because he’s a Catholic. He’s such a poor Catholic. Now, if it were Bobby, I could understand it!” Like the leaders of the civil rights and abolitionist movements, RFK was comfortable with making moral arguments that draw upon spiritual language that has deep meaning to millions of Americans. Today, Mayor Pete Buttigieg articulates the fight for gay rights in religious terms, telling the Mike Pences of the world, “If you have a problem with who I am, your problem is not with me. Your quarrel, sir, is with my creator.”

5. He continually underlined the dignity of work.

RFK denounced welfare not because “welfare queens” were abusing the system, as Ronald Reagan would later claim, but because RFK believed welfare was “demeaning and destructive of the human being and of his family.” Kennedy instead pledged “jobs for all of our people” so that a job recipient could say, “I helped to build this country. I am a participant in its greatest public venture.” RFK realized that unemployment had civic as well as material costs. “Unemployment means having nothing to do—which means having nothing to do with the rest of us.” Today, Mayor Mike Bloomberg notes he did not inherit his wealth, the way Donald Trump did. “I’m not the smartest guy in the room, but nobody’s going to outwork me,” Bloomberg says.

6. He denounced excessive materialism

In one of Kennedy’s most famous speeches, he put material interests in their proper context. “[The] Gross National Product counts air pollution and cigarette advertising, and ambulances to clear our highways of carnage.… Yet the gross national product does not allow for the health of our children, the quality of their education or the joy of their play…. It can tell us everything about America except why we are proud that we are Americans.”

Today, Americans still believe deeply that material comfort is only a piece of what makes life fulfilling. In focus groups, where participants are given a stack of 50 “Picture Your Legacy™Cards” with different images and asked to pick the three that least reflect their values, people from all backgrounds invariably choose the images of materialistic items such as mansions, yachts, and skyscrapers. As entrepreneur Andrew Yang notes, “There’s a real loss of meaning for many people in the country.”

7. He emphasized the importance of respecting the law.

Unlike other candidates in 1968, RFK saw no contradiction between supporting civil rights and maintaining law and order. He reminded voters that as the US attorney general he had been the nation’s “chief law enforcement officer” and during the campaign, RFK told his media adviser, “I want a law and order ad. Why don’t we have a law and order ad?”

Today, progressives should reject the racially charged use of “law and order” employed by some conservatives and reinvent the term to mean a society that embraces laws and wants to maintain order, alongside justice—lest voters incorrectly conclude that progressives find lawlessness and disorder acceptable. Senator Amy Klobachar, for example, takes a generally compassionate view toward immigrants, noting, “immigrants don’t diminish America; they are America.” But she couples that view with respect for the law, which she applies to American employers, declaring that there should be “no amnesty for companies hiring illegal immigrants.”

By recommitting to and reinterpreting deeply and broadly held values that conservative politicians have hijacked, progressives today could get out of the limiting “more left vs. more centrist” box to make inroads on reinventing the Bobby Kennedy coalition—and begin to unite the country.