A coalition of DFL legislators is launching an effort to ensure that all workers in the state have paid family and sick leave, an issue emerging as a top priority for Democrats this legislative session.

Assistant Senate Majority Leader Katie Sieben, DFL-Cottage Grove, said Monday it would help families in challenging financial times.

“A paid family leave program in Minnesota will ensure that workers have some degree of security when a major life event occurs,” said Sieben, the chief Senate sponsor. “Families need time together when a major life event occurs. … It seems to me this is the most basic family value.”

Nearly 136,000 workers in Minnesota would benefit from the program each year, according to a study conducted by the University of Minnesota and the Institute for Women’s Policy Research. Up to $461.8 million in benefits would be paid out a year.

Republicans who control the state House say they are working on their own proposal, which is expected to be released in coming weeks. House Republicans said finding a workable measure will require bipartisan support.

Opposition was voiced by Cam Winton of the Minnesota Chamber of Commerce. While sympathetic with the plan’s goal, Winton said it could rob employers of flexibility. “The best way to foster greater access to leave is with flexible, voluntary approaches rather than with a one-size-fits-all mandate from government paid for with a brand-new tax,” Winton said in a statement.

Democrats unveiled the proposal the day before the start of the 2016 legislative session, when legislators will debate what to do with a $900 million projected budget surplus.

The proposal would establish a state insurance program that would offer workers in the state a portion of their pay for up to 12 weeks a year for pregnancy or medical issues. Workers would also receive 12 weeks of paid leave to care for a sick family or to care for a newborn child.

Employers and employees would share the costs of the program, which is estimated to cost workers earning the state median income about $1.70 a week. Workers would be reimbursed up to 80 percent of their pay while taking leave.

The Legislature would need to come up with some start-up money, but Senate staff said they won’t know how much until fiscal analysts can determine the initial cost.

The workforce plan comes just a month after DFL Gov. Mark Dayton proposed a similar program for 35,000 state employees.

Joining Sieben in Monday’s news conference were other cosponsors, including Rep. Jason Metsa, DFL-Virginia and Rep. Peggy Flanagan, DFL-St. Louis Park, and other supporters

Senate Majority Leader Tom Bakk, DFL-Cook, lent the plan his support, saying in a statement that “paid family and medical leave modernizes our workplaces and will make Minnesota more attractive state for workers.”

Flanagan, who said she was able to take time off work to care for her newborn child, said it’s un-Minnesotan that so many are not able to do the same.

If approved, Minnesota would join California, New Jersey and Rhode Island, states with similar laws on the books. Two other states — Hawaii and New York — offer paid medical leave only.

While the program would be mandatory for employers and employees to participate in, it would not be required for employers with existing paid family and sick leave policies. The bill would also protect employees from retaliation from employers after returning to work.

Employers with paid family and sick leave policies that match or surpass the proposed state insurance plan would be exempt from the new law.

Christopher Aadland is a University of Minnesota student on assignment for the Star Tribune.

Star Tribune staff writer Ricardo Lopez contributed to this report.