Minnesota's health insurance exchange will offer the lowest premiums of any in the nation, according to a new federal analysis of offerings around the country.

Premiums for the cheapest — or "bronze" — insurance plan offered through MNsure will cost an average of $144 per month before any tax breaks or subsidies, the U.S. Department of Health and Human Services reported Wednesday. That compares with a national average of $249 per month.

Bolstered by the news after several weeks of glitches and growing pains, officials at MNsure said Wednesday that the new online marketplace is on track to start enrolling customers as scheduled Tuesday.

"Things are looking very good, the system is secure," executive director April Todd-Malmlov said at a MNsure board meeting. "At this point we feel that we have mitigated all of the areas that we've been tracking, and then we will be ready to go."

The exchanges, meant to allow people to log on and comparison shop the way they buy plane tickets or hotel rooms, are critical to the Obama administration's effort to make it simple and relatively affordable to find coverage.

But details on the coverages Minnesotans will receive are still unclear. A bronze plan must cover 60 percent of medical costs, a silver plan must cover 70 percent and a gold plan must cover 80 percent.

However, premiums, deductibles and out-of-pocket maximums will vary by health insurance company, even within the various categories. In general, lower premiums will come with higher out-of-pocket costs.

Gov. Mark Dayton trumpeted the news that the Minnesota exchange's average rates will be the lowest in the nation.

"There's plenty of credit to go around. I'm not claiming credit," Dayton said, pointing to state officials, insurers and workers who have scrambled to put the complex system together in the six months since it was signed into law. "We should be celebrating the fact … that employees and employers, especially small-business employers, can get the lowest rates of any state in the nation for the health care for the people who work for them."

Republican legislators were unimpressed. MNsure rates will vary not just by insurance provider but by geography, with the highest premiums in the southeast corner of the state, which includes the home district of Rep. Greg Davids, R-Preston.

"As long as Minnesotans can't purchase health insurance across state lines, today's 'announcement' means very little," Davids said in a statement. "Minnesotans will still be forced to pay more for fewer options under Democrats' insurance exchange than they do in the private market here in Minnesota. Hardworking Minnesota families don't need more misleading information from Gov. Dayton and Democratic legislators about the cost of their new state agency."

The federal analysis found that insurance through MNsure will cost less than insurance through other state-run exchanges or the marketplaces that will be operated by the federal government in 36 states.

Premiums through the exchanges in North Dakota, South Dakota and Wisconsin will cost more than the national average, while Iowa's exchange will offer bronze plans at an average rate of $212 per month, ranking 11th-lowest in the nation.

In a quiet board meeting Wednesday a week before the program's launch — what MNsure board Chairman Brian Beutner called the "calm before the storm" — most of the discussion was about how the agency will track enrollment and report it to the board of directors.

MNsure has projected that it will enroll 930,000 people in 2014. By 2016, the state expects 1.3 million to enroll — about one in five Minnesotans.

Todd-Malmlov told the board that her agency is already tracking calls to its call center and offered to give board members daily updates.

But Beutner wants the board to get reports on problems and how they're resolved. "Just some general sense of the ongoing fixes, I think would be helpful as people reach out to us and say 'How's it going,' " Beutner said. "It just starts to build that confidence in the system, because we know there will be issues, and we know there will be ongoing fixes, and that's part of the story."

Lucinda Jesson, a board member and Dayton's human services commissioner, said it will be important to track accounts created and enrollment geographically in order to figure out how much progress the program is making in underserved areas and in minority communities so the agency can shift focus when necessary.

"If we know that we're not meeting our enrollment targets in Beltrami County, where we know there are a lot of people without insurance, but we're making more progress in Winona, then we need to shift resources," Jesson said.

Beutner then asked what the enrollment targets are. Todd-Malmlov said MNsure has general monthly goals, but didn't share them, and referred to the earlier projection of 930,000 enrolling in 2014.

"What we were projecting to come in from the call center is really close to what we're getting," Todd-Malmlov said. "So I do think that we're in the ballpark of what we were thinking."