ST. PAUL — State health officials are in the midst of a massive transition of residents on public health programs, shifting hundreds of thousands of low-income people to new coverage plans as the state aims to book millions of dollars in savings.

The unprecedented effort is a byproduct of a competitive bid for companies to cover MinnesotaCare and Medical Assistance enrollees — the first statewide offer for those massive contracts. The big loser in that process was UCare, which lost its contracts in all but one county, forcing its 350,000-plus customers to pick new plans for next year — and perhaps leave behind their current doctors.

A top state official overseeing the transition said this week that the estimated $450 million in savings from the bidding far outweigh the extra costs of the shift, like additional call center staff to answer questions from confused consumers. Department of Human Services Assistant Commissioner Nathan Moracco pegged the likely costs at somewhere around $2 million.

“We’re mindful that it’s going to increase the cost. We’re not sure ultimately what’s going to be needed,” Moracco said.

Re-enrolling residents is an annual part of the state’s role in running subsidized health care programs. Minnesota contracts with health care providers to cover the low-income residents on Medical Assistance — the state’s version of Medicaid — and those on MinnesotaCare, a program for the “working poor.”

But while the state has usually dealt with about 80,000 people picking new plans each year, they’re tasked with shifting more than 400,000 to new plans for next year — largely due to UCare being taken out of the mix. The Department of Human Services sent out notices to all of its public program enrollees this fall, asking them to choose a new plan by Dec. 11 for coverage next year.

Guiding the migration to new plans is just the latest challenge stemming from the competitive bid process that eliminated UCare. The Minneapolis company sued the state over the decision, alleging that it was arbitrarily cut out of the process. UCare later dropped the lawsuit. Another lawsuit from a UCare customer is still pending in Ramsey County District Court.

UCare touched on the difficulty of moving its customers to new plans in its lawsuit, calling it “the largest disruption in public health insurance plans in state history.”

Minnesota’s counties have traditionally handled the churn of residents moving between plans. When news of UCare’s removal spread this summer, those counties wondered how they’d handle a flood of more than 350,000 UCare customers statewide scrambling to pick new plans.

“We certainly raised a lot of questions and concerns with DHS about how we were going to manage that,” said Julie Ring, executive director at the Association of Minnesota Counties.

But in Ramsey County — where UCare has been the major provider of public programs — and in counties across the state, health care officials are relieved that the state has taken up much of the burden. The state is handling the shift of more than 60,000 Ramsey County residents to new plans, county Director of Community Human Services Meghan Mohs said.

Some public program recipients could have problems if they don’t actively pick a new plan accepted by their current doctors. For those who don’t, the state automatically assigns them the highest-ranked plan in their county.