Despite months of glitches, embarrassments and finger pointing, Minnesota's health insurance exchange is on the verge of reaching its goal to sign up 135,000 people by March 31.

More than 1,000 Minnesotans are enrolling daily as MNsure enters the final days for consumers to buy insurance or face a financial penalty. Enrollment in government programs for those with low incomes has been particularly strong, offsetting figures for commercial health plans that are much lower than expected.

"We find ourselves constantly checking our phones for the latest numbers," said MNsure interim CEO Scott Leitz, who took the helm in mid-December amid a near-meltdown of the computer system.

It's still not known how many of Minnesota's 445,000 uninsured will find coverage through the exchange or other means, a key goal of the federal health law; MNsure hasn't released data on that measure to date. Ultimately, MNsure aims to connect more than 1 million residents with coverage over the next three years.

But meeting its open enrollment goals, which were revised downward shortly after MNsure's launch in October, looked like a tall challenge in the early days. The new agency lumbered under technical glitches and a leadership change during its first six months.

MIT health economist Jonathan Gruber, who authored a report for MNsure that was used to set enrollment goals, said MNsure's gains are notable.

"I'm impressed with the numbers in Minnesota, given what a mess the website has been," he said. "I would have expected to see, like zero, from what I've read in the news."

There has been a late enrollment surge nationwide, as well. More than 5 million Americans have bought insurance through federal and state exchanges, federal officials announced last week. That is still about 1 million shy of the Obama administration's goal, but the gap has narrowed as technical problems on the federal website have abated. Many of the 14 states and District of Columbia that built their own marketplaces got off to a halting start, but now are generally outperforming states relying on the federal exchange. Minnesota, which received $155 million in federal grants to build, market and staff the MNsure exchange, has been somewhere in the middle in terms of enrollment.

Some state exchanges, such as New York, Connecticut and Vermont, are meeting enrollment goals and reaching a high percentage of those in need. Others, such as Hawaii and Nevada, are lagging.

In Minnesota, the mix of plans sold through the exchange has been much different from expected. About half as many Minnesotans as first projected in October have bought private coverage through MNsure, and interest from small businesses has been nominal.

Eventually, it will be important to sell more commercial plans, because a key funding source for MNsure is a fee insurers pay based on premiums for private insurance.

More than five times more Minnesotans than projected have gained health coverage under Medical Assistance, the state's version of Medicaid for the poor. Public health leaders see this as an encouraging sign, as 60 percent of the uninsured are eligible for one of the state's public programs but haven't signed up.

"We used to talk about 'no wrong door,' " said Lynn Blewett, who tracks insurance trends as director of the State Health Access Data Center. "So if overall, we're reducing the uninsured rate by getting people on Medicaid, in addition to MinnesotaCare, in addition to the exchange, it's good for the state."

State officials credit the surge to outreach efforts by county workers and MNsure-certified navigators, who have mastered the quirks of the website and filled out some 26,000 paper applications.

Department of Human Services Commissioner Lucinda Jesson said the state's decision to expand Medicaid to include single adults without children has helped drive up the numbers.

She also suspects the health law's individual mandate has played a role. Under the Affordable Care Act, consumers without private insurance after March 31 could be required to pay a tax penalty of $95 or 1 percent of household income, whichever is greater.

"While some people have struggled to get through MNsure, overall it's a lot easier to enroll in a public program through MNsure than it was using the lengthy process we had in the past," Jesson said. "I think the mandate is pushing some people who are eligible to take that ­additional step and enroll."

State Rep. Tara Mack, R-Apple Valley, said MNsure's enrollment gains "are a victory that we can all rally around." But she worries that early problems with the website and a general lack of awareness will sock too many Minnesotans with penalties they don't deserve.

"We can acknowledge victories, but we need to be honest about needed changes," said Mack, GOP leader of the health and human services policy committee. "We just need this thing to work, and we need it to work well and do what it was supposed to do for Minnesotans."

In a March 18 letter to Gov. Mark Dayton, Mack and Rep. Joe Hoppe, R-Chaska, called on the governor to delay the penalty.

MNsure announced Monday that it would allow flexibility to some people who can show a good faith effort that they were trying to buy coverage, but were stymied by technical issues.

In a statement, Dayton said: "I strongly support MNsure's decision to extend the enrollment period for Minnesotans who have tried to enroll in health care coverage by the March 31st deadline."

To skeptics, it seems a long-shot that some 1.2 million Minnesotans, or nearly 1 in 5 residents, will buy insurance through the MNsure website when it's fully operational in 2016.

"The numbers were always inflated … and MNsure never came clean with the public," said PreferredOne CEO Marcus Merz, whose low-priced health plans have enrolled nearly 6 in 10 people on the exchange. "There was so much happy talk, this thing took on a life of its own. And now they'll be coming in 1.1 million people short."

MNsure's supporters are preaching patience.

"This is not a day-to-day, or week-to-week, or even month-to-month process," said Gruber, Obama's health adviser and a key architect of the Massachusett's exchange.

"This is a three-year process. That's how long it took us to get fully ramped up in Massachusetts. That's what the Congressional Budget Office estimated to the full ramp-up of Obamacare."