As the 2015 Legislature commenced, Capitol speculators wondered whether rookie House Speaker Kurt Daudt could keep a fracture-prone new Republican majority together. He's got a scary rift to bridge between exurban Tea Partiers and conventional Greater Minnesota Republicans, the chatterers said. It's gonna be tough for the three-termer from Crown.

As the 2015 session lurched last week to a special-session finish, such talk had almost completely flipped to its partisan inverse: How will Senate DFL Majority Leader Tom Bakk cope with a gaping division between metro and rural/Iron Range members of his caucus? Can the eight-termer from Cook quiet the discontent that has been rumbling since the regular session ended?

Rural/urban tension is nothing new in Minnesota politics, as the very name of the Democratic-Farmer-Labor Party implies. Through the years, that party's most memorable internal battles — abortion, guns, motorboats in the BWCA — were fought along an outstate/metro fault line.

The spat over this year's omnibus agriculture/environment/natural resources bill hasn't risen to the internecine intensity of those historic brawls. But on May 18, when the 39 Senate DFLers split 10 in favor and 29 against a bill DFL Gov. Mark Dayton later vetoed, they put a family quarrel over environmental protection on vivid display.

Those who voted yes sided with all but one of the Senate Republicans voting that day. Those who voted no were bucking Bakk, who had done much of the assembly of the bill during closed-door negotiations with Daudt. The bill's critics objected to a long list of regulation-weakening measures evidently acceptable to Bakk and his nine allied DFLers, all but one of whom represent nonmetro districts.

A particular sore point was hard-to-spot language exempting nonferrous mining from solid waste rules. It was a provision that had never been introduced as a bill or heard in any legislative committee before its appearance on May 18.

Another rub: elimination of the 48-year-old Citizens' Board of the Pollution Control Agency, which employed language that had not been passed by either legislative chamber. The board is under fire for seeking an environmental-impact statement from a proposed dairy megafarm last year.

The Senate DFLers who voted no that day would have been unhappy had a Republican majority or Republican governor forced such measures into an omnibus bill. The fact that their own caucus leader and his adjacent-district ally, conference committee co-chair David Tomassoni, DFL-Chisholm, had fingerprints on them made "unhappy" an understatement.

The DFLer who led the May 18 floor attack on the bill is known to Minnesotans of long political memory — state Sen. John Marty, DFL-Roseville. Though he chairs the Senate's environment and energy policy panel, he was largely frozen out of the dealmaking that crafted the omnibus ag/enviro bill.

Twenty-one years ago, Marty was his party's up-and-coming candidate for governor. It was his misfortune to run against incumbent Republican Gov. Arne Carlson, whose popularity swelled in 1994 as he fended off a primary challenge from the GOP hard right.

"I got clobbered," Marty said last week. For a long time thereafter, "I was punished for that. In politics, you are worthless if you don't win an election."

Today at age 58 and serving his ninth term, Marty is far from worthless. He has become the Senate's voice of conscience, known for sounding off when special interests aren't in sync with the public interest. One might conclude that spending time in political purgatory early in his career built his courage.

It would be a stretch to cast Marty as Bakk's rival for caucus leadership. Others may make that fight. But Marty has emerged in recent weeks as a potent critic of the environmental policies Bakk accepted and the dealmaking process that produced the year's final bills.

Too often, Marty says, Senate negotiators agreed to GOP-backed policy in exchange for more spending than House Republicans initially sought. Those policy measures went into must-pass budget bills, ones that have to be set in law by July 1 to avert a government shutdown. The budget thus functioned as a hostage, used to compel votes for policies that, in isolation, would not have passed muster in the Senate, Marty believes, despite its metro/outstate divide.

"We can deal with the differences between the metro and the rural areas of the state," he said. "We always have. Concern for this state's natural resources polls well in every part of the state. You can have honest disagreements about particular policies and still find a way forward. But when people are playing games with the process, that's what tears apart a caucus and a party."

Marty favors a change in legislative rules to segregate policymaking from budget-setting. Policy matters should be addressed in separate bills, he argues.

The idea isn't original with him. According to the National Conference of State Legislatures, seven states go so far as to require their legislatures to work exclusively on budgetary matters in one session and reserve policy bills for a subsequent one. Those restrictions typically aren't absolute; most allow exceptions with a supermajority vote.

Ironically, the other DFL senator who has voiced interest in separating policy and budgeting bills is Tom Bakk. Weeks before the session ended, he sent Senate committee chairs a memo urging them to keep policy matters out of budget bills. Policy differences between the House and Senate only serve to complicate budget negotiations, he advised.

One sign of the tension that has built within the Senate majority caucus is that the sincerity of that memo is now in question.

Those hard feelings made a Bakk-Marty alliance on procedural reform or much of anything else seem far-fetched last week. Then again, Bakk is the son of a Lutheran camp director, and Marty is the son of a leading Lutheran theologian. They likely share a few notions about repentance, forgiveness and redemption, and those concepts can produce surprising fruit.

Lori Sturdevant, an editorial writer and columnist, is at lsturdevant@startribune.com.