Enrollment activity is picking up at the state’s MNsure health insurance exchange in advance of Sunday’s deadline for individuals to buy 2018 coverage.

On Monday, the number of online shopping sessions at the MNsure website hit its highest point since last month’s deadline for coverage that started Jan. 1, said Allison O’Toole, the MNsure chief executive. People who sign up for coverage between now and Sunday would have health plan coverage as of Feb. 1.

The exchange also is seeing a growing number of website users who have put items in their online “shopping baskets” actually complete their purchases.

“We are ahead of where we were last year at this time,” O’Toole said during a MNsure board meeting in St. Paul. But she cautioned: “At this time last year we had about three more weeks of open enrollment.”

Minnesota launched the MNsure exchange to implement the federal Affordable Care Act (ACA), sometimes called Obamacare, which brought sweeping changes to the market where self-employed people and those who don’t get coverage from their employer buy health insurance. About 166,000 people buy coverage in the Minnesota market, which primarily serves people under age 65.

Last year, 114,810 people signed up for individual policies via MNsure during an open enrollment period that stretched into early February. As of Tuesday, the sign-up tally for 2018 coverage was 111,667 people.

MNsure doesn’t have a goal in terms of sign-ups, but rather a budget projection based on an estimate for the number of people are actually buying 2018 coverage.

Since open enrollment began in November, exchange officials have said repeatedly the shopping volume thus far suggests MNsure is on track to meet or possibly exceed the current goal for paying customers, which is roughly 4 percent more than the number buying 2017 coverage.

They have noted a relatively large share of those signing up for coverage are new to the exchange, saying it’s a good sign for growth. As of Tuesday, the enrollment tally included 30,259 new enrollees.

The optimism about meeting or exceeding the budget goal continued Wednesday, said spokesman Jeremy Drucker. He added: “We’re going to continue to monitor and things will come into sharper focus in early spring.”

Minnesota is in the minority of states in operating its own health insurance exchange, rather than directing residents to the federal government’s HealthCare.gov website. Open enrollment through the federal website closed last month, and the sign-up volume in states that use HealthCare.gov was down about 5 percent.

Analysts attributed the decline to the shorter open enrollment period plus uncertainty about how efforts to repeal and replace the ACA would impact the market — while also noting that it wasn’t as steep a drop as expected.

On Wednesday, MNsure board chairman Phil Norrgard noted the federal numbers during Wednesday’s board meeting, and said they suggest the showing in Minnesota is particularly strong.

Minnesota’s market has been unusual since major ACA changes kicked in during 2014.

The volume of people buying through the exchange has been relatively low because of the state’s MinnesotaCare program. In addition, Minnesota has had a relatively large “off-exchange” market, where people buy individual policies directly from carriers or through brokers.

While the volume of people buying through MNsure for 2018 seems to be holding steady or growing, it’s unclear what enrollment activity has been like in the off-exchange market. Across the country, relatively small enrollment numbers is one reason some insurers have backed away from the market, which also has been the source of red ink for many carriers.

Overall, Minnesota’s individual market is significantly smaller than it was in 2014, and the number of people buying private insurance through the exchange has fallen far short of original projections.

MNsure will extend hours at its call center through Sunday to handle an expected surge in sign-up activity.