ST. PAUL, Minn. - Leaning into friendlier political terrain, a union for Minnesota nurses renewed its call Wednesday for state lawmakers to establish requirements that would dictate how hospitals staff their emergency rooms, childbirth wards and other units.

The drive to impose minimum staffing levels in law has the union and hospitals bracing for a contentious fight, one that could also expose simmering divides between nurses who are represented by the Minnesota Nurses Association and those who are not. Minnesota would join California as the only states with such a law if new Democratic majorities and Gov. Mark Dayton go along.

The union led off its Capitol push with nurses offering testimonials about being forced to juggle too many patients at once. Sandra Anderson, a nurse from Wyoming, Minn., said patients are being exposed to too much risk.

"Beyond the closed doors, behind the curtains, below the shiny brass awards for safety, nurses witness too much suffering and too many errors," Anderson said. "We catch way too many near-misses because we are stretched dangerously thin."

The "Standard of Care" proposal seeks to devise and enact hospital-by-hospital staffing requirements over the next year. Precise head counts would vary by the severity of patient illness, the type of unit, the required skill level and the amount of surveillance patients need. The standards would be drawn from recommendations of various professional groups or developed by a working group overseen by the state commissioner of health.

The plan would establish a system of record keeping for hospitals and potential punishments for those that fall short of the standards. Staffing levels would have to be posted in waiting areas for staff, patients and the public. Annual reports from hospitals would include details on the hours-per-patient that nurses work.

Linda Hamilton, a registered nurse and the union's president, rejected suggestions that the goal was to boost the number of nursing jobs. State Rep. Joe Atkins, who is sponsoring the bill, said he wants to help hospitals come up with a solution, not antagonize them.

"For decades we have debated per pupil teacher ratios in schools because education is so important and yet we really haven't had a good conversation about patient-nurse staffing ratios in our hospitals where life or death is an issue," said Atkins, DFL-Inver Grove Heights.

But the state's hospitals have been building a resistance effort. The Minnesota Hospital Association has a splashy website featuring video of nurses vouching for flexibility rather than hard-and-fast ratios. The nurses association represents only a fraction of the care staff in hospitals around the state, but the requirements they're seeking would apply across the board.

Mary Krinkie, a vice president of the Minnesota Hospital Association, said meeting proposed staffing requirements could cause nursing shortages at small-town clinics and long-term care facilities because hospitals would step up efforts to lure nurses away to meet staffing quotas.

"These decisions should be made by health care professionals at the bedside: doctors, nurses, respiratory therapists, all of our caregivers. They shouldn't be made by the Legislature," Krinkie said. "Quite frankly, we have enough government involvement in health care."

The union has long made a case for mandatory staffing ratios based on the number of patients and type of unit. It waged a short strike at some Twin Cities hospitals in 2010 to press the point. But the group has found little traction in the Legislature before.

Last year, the union was more active in state political campaigns.

The Minnesota Nurses Association's political committee wrote a combined $55,000 in checks to the House and Senate Democratic caucuses in last year's campaign, more than twice what the main hospital group contributed. The nurses spent an additional $200,000 on individual races to help their political allies, dwarfing the involvement of the hospital group.

The new House majority leader, Democrat Erin Murphy of St. Paul, is a registered nurse who used to be a lobbyist and organizer for the nurses association.

For his part, Dayton declined Wednesday to take a stand on the proposal. He told reporters he too wants to ensure sufficient nursing in care facilities but said he wasn't familiar enough with the latest proposal to commit either way.