Albert R. Hunt is a Bloomberg Opinion columnist covering politics and policy. He was the executive editor of Bloomberg News, before which he was a reporter, bureau chief and executive Washington editor at the Wall Street Journal. Read more opinion LISTEN TO ARTICLE 5:08 SHARE THIS ARTICLE Share Tweet Post Email

Photographer: Daniel Kucin Jr./Icon Sportswire via Getty Images Photographer: Daniel Kucin Jr./Icon Sportswire via Getty Images

If you started reporting on American politics in the 1970s and 1980s, Minnesota was the place to look for gold-standard politicians. Democrats included Hubert Humphrey, Walter Mondale, Donald Fraser and Tim Penny. The Republicans had Al Quie, Bill Frenzel and Vin Weber.

Covering a personal and philosophical spectrum, they were serious, productive politicians. Each could be a fierce partisan, yet all enjoyed bipartisan respect.

That's a Minnesota that wasn't recognizable when I visited last week. This month, the Republican and Democratic nominating conventions rejected candidates considered the most electable in November, former Republican Governor Tim Pawlenty and Democratic Representative Tim Walz, though August primaries could reverse those results. In the battle for the House of Representatives, two Republican incumbents representing suburban seats are endangered, as are two Democratic-held seats in more rural regions.

Political polarization is pervasive, exacerbated by President Donald Trump. Minnesota has had its political eruptions before, as when it elected the pro wrestler Jesse Ventura as governor in 1998. But the strains have grown even since then and comity has diminished.

This reflects national trends, but also is a product of the state's precinct caucus system, which leads up to state party conventions and their endorsements. It created grassroots participation that made the Democratic-Farmer-Labor Party one of the most successful political organizations in the country. Today, both parties are heavily influenced by activists more intent on pushing ideological agendas than on winning or creating governing coalitions.

"The precinct caucus system today rewards the radicals," said Mike Freeman, the county attorney in Minneapolis and son of a celebrated Democratic governor. "It pushes Republicans to the right, Democrats to the left." Last week, both Pawlenty and Peggy Flanagan, Walz's running mate, told me it's time to end the precinct caucus process.

The House races reflect the changing politics. Republicans are confident of winning the Democratic-held seat in the working class Iron Range region north of Duluth, where Trump campaigned last week. Democrats think they'll hold the southern Minnesota district represented by Walz, while up for grabs are two Republican suburban districts where Trump is not an asset.

If this seems crazy-quilt, the governor's race is even crazier. Walz, who represents a moderate, partly rural district stretching across the southern part of the state, picked Flanagan, a state legislator and rising liberal star, who'd be the first Native American elected statewide. In an interview at a union picnic, Walz noted that Trump came within 44,000 votes of being the first Republican presidential candidate to carry Minnesota since 1972.

"We can't be seen as just the urban party," he said, a view shared by one of his most prominent supporters, former Vice President Walter Mondale.

But Walz was upset at the state convention by a liberal St. Paul state legislator, Erin Murphy, who picked another liberal woman as her running mate. Murphy is a serious legislator who veers left, espousing a government-run health-care system. She thinks she can beat Walz by stressing some of the pro-gun votes he cast in Congress.

Few believed she could until Attorney General Lori Swanson, who had said she was running for re-election, suddenly threw the race into turmoil by jumping into the governor's contest. She picked as her running mate the congressman from the Iron Range, Rick Nolan, who a few months earlier had endorsed Walz and said he was retiring to spend more time with his ailing daughter. Some analysts believe this ticket could siphon enough votes from Walz to give Murphy the win in the Aug. 14 primary. That would be the Repubicans' dream.

Yet the GOP schisms may be as real. Pawlenty, a two-term former governor, came home after five years as a Wall Street lobbyist in Washington to try to reclaim his old office. Establishment Republicans were pleased, but the party's convention chose Jeff Johnson, a county commissioner and Trump enthusiast who dubbed Pawlenty anti-Trump and anti-populist.

Pawlenty had backed Florida Senator Marco Rubio in the 2016 Republican presidential primary. Johnson was Rubio's state chair before switching his support to Texas Senator Ted Cruz.

During an interview at a coffee shop in his hometown of Eagan, Pawlenty said he was Minnesota's "most conservative governor" in 50 years and was known as a "Sam's Club Republican" rather than the country club kind.

But Trump makes the Pawlenty camp nervous. The former governor didn't go to the Trump rally in Duluth, though his running mate did. Asked about Trump, he said: "I agree with most of what the president has done. I give him credit for being bold." The White House has said that Trump will stay out of the Minnesota primary, but he could tweet out something hostile tomorrow.

My hunch is that the fall contest will pit Walz against Pawlenty, which would be a turn toward the glory political days.

But it's hard to be sure. There's an unpredictable streak among Gopher State voters. At the union picnic last week, a building trades worker who voted for Trump and still supports him told me he is enthusiastically backing Walz. The next day, a Lyft driver, part African-American, part Latino, told me he's a conservative who doesn't like Trump. He's going to volunteer for Pawlenty.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.