A new biography relates that before Don Fraser was Minneapolis’s longest-serving mayor and an effective member of Congress, he was an eight-year member of the Minnesota Senate. From 1954 to 1962, he functioned as a de facto leader of the Liberal (DFL) caucus and, though in the minority, sponsored such enduring measures as the 1961 statute outlawing racial discrimination in housing.

That career sequence, nicely described in Minneapolis historian Iric Nathanson’s new book by Nodin Press, “Don Fraser: Minneasota’s Quiet Crusader,” was a fairly typical Minnesota political life story — until lately.

For most of this state’s 160-year history, the Legislature has been the training-and-proving ground for this state’s members of the U.S. House. When congressional seats became vacant, political parties regularly tapped legislators with a few terms to their credit. Parties looked for legislators who had demonstrated an ability to serve constituents, build coalitions among colleagues, carry bills to enactment and — dare I say — compromise.

Fraser did all those things, the book reports. Though only 30 years old when elected, he was already a veteran of DFL politics and a personal ally of Gov. Orville Freeman. That made him a standout in what was, in the 1950s, a crusty old-boys club.

But it didn’t assure success. Fraser had to learn to stay in touch with the people in his district, build relationships with other legislators and translate principles into workable policy.

“The Legislature taught him how to move bills,” Nathanson told me last week. With Conservatives [Republicans] in charge of the Senate, “he had to learn how to balance being a forceful voice in his own party with working with the other side.” The state Fair Housing Act likely would not have become law in 1961 had Fraser not learned that lesson well. Among his allies on that bill were Republican Gov. Elmer L. Andersen and the Senate’s Conservative titan, Gordon Rosenmeier of Little Falls.

Similar stories might be told about a host of Minnesota legislators-cum-congressmen. They’re so numerous that naming only a few would generate a gusher of e-mails chiding me for omissions. Suffice to say that the pattern is old and bipartisan, and that among the eight Minnesotans in today’s U.S. House, six previously served multiple terms in the Legislature.

But the pattern didn’t hold the last time a Minnesota congressional seat became vacant, in 2016. In the weeks after GOP U.S. Rep. John Kline’s retirement, a number of legislators quickly announced that they would not try to succeed him. Farmington GOP Rep. Pat Garofalo memorably said he would “rather stick a fork in my eye than run for Congress.”

The Second District seat ultimately went to Republican Jason Lewis, a radio talk-show host with no previous election certificate to his name. He possessed traits that parties lately seem to favor as much or more than legislative service — celebrity status, outspoken ideology, attention-getting style, and deep pockets or a knack for fundraising.

A similar flurry of non-candidacy announcements followed U.S. Rep. Rick Nolan’s retirement announcement in the Eighth District earlier this month. One former legislator, DFLer Joe Radinovich, jumped in. He served but one term in the state House and comes to the contest by way of Minneapolis, where he had a brief stint as Mayor Jacob Frey’s chief of staff. Other legislators are said to be “considering,” but with each passing day, their considerations seem less likely to lead to candidacies.

The other vacant seat this year is in the First District, where dozen-year U.S. Rep. Tim Walz is running for governor. On the DFL side, former state Sen. Vicki Jensen of Owatonna has six opponents, none with legislative service on his vita. Jensen’s legislative credentials and the rest’s lack thereof could be a factor in their contest.

But the better indicator of whether Minnesotans still like some legislative seasoning in their congressional candidates will come in the First District Republican contest — Jim Hagedorn, a former federal agency official and Walz’s 2014 and 2016 opponent, vs. Rochester state Sen. Carla Nelson, a four-term legislator and chair of the powerful Senate E-12 Finance Committee.

Nelson, a former teacher and small-business owner, was a late arriver to the race. The illness and death of her father last year delayed her entry.

In addition, she said last week, “I did think about” the reasons other legislators have cited for not running for Congress. The job’s expectations have come to include weekly commuting from Minnesota to Washington, frequent public appearances at home and constant fundraising. In districts that can swing one party to the other, as the First is wont to do, candidates can expect that millions of dollars will be spent to besmirch their records and reputations. Even for stouthearted people, congressional service is a daunting prospect.

What tipped Nelson’s decision, she said, is that “I believe in our country. I could not be content to sit on the sidelines, not when the need is so great in Washington for people who are truly about serving others and getting things done.”

She talks at length about the value of legislative service, as might someone who plans to make that credential a talking point in a primary contest. Legislators learn they must listen to the people they represent, she said. They discover that no legislator can be effective alone. They find that positive relationships are essential to achievement, and that honesty is essential to good relations. “Your word is the commodity you are measured upon here,” she said.

Good legislators realize that at times, representing their districts requires standing apart from their parties — and that while doing so is not easy, it’s what’s required for representative democracy to work.

Nelson says she inherited “a servant’s heart” from her parents, who were both teachers. But she learned how to be a lawmaker at the Legislature. The next measure of how much that matters to Minnesota voters will come from First District Republicans on Aug. 14, primary election day.

Lori Sturdevant is a Star Tribune editorial writer. She is at lsturdevant@startribune.com.