Allison O'Toole, MNsure's interim chief executive, was named permanent CEO on Wednesday afternoon, even though she wasn't even a candidate for the job until last week.

Two weeks ago, the MNsure board said a national search for the top spot at Minnesota's health insurance exchange had generated the name of just one finalist — a Twin Cities executive named Mark Nyquist.

At the time, MNsure board chairman Peter Benner mentioned Nyquist's work with some of the largest companies in the region including Cargill, General Mills and UnitedHealth Group.

But board members became concerned about the need for continuity at MNsure, Benner told reporters Wednesday, and a chief executive who could hit the ground running on the first day of the job.

"There clearly was going to be a learning curve," Benner said of Nyquist, who did not return phone calls seeking comment.

Benner said that Nyquist withdrew his name from consideration on Wednesday morning. In the afternoon, the board voted to give the job to O'Toole, who has been interim chief executive since May.

She is the third top executive at MNsure since the organization was created through legislation that was signed into law in 2013.

"We've made progress in the last six months, and I want to help the organization continue in that direction," O'Toole said.

Minnesota launched the MNsure exchange in October 2013 to implement the federal Affordable Care Act, which requires almost all Americans to have health insurance or pay a tax penalty. After a rocky rollout, the exchange has improved but is still short of enrollment goals.

MNsure launched its search following the departure in May of previous chief executive Scott Leitz. O'Toole had said she wasn't interested in the permanent CEO position, but "gave it fresh consideration," she said, when board members approached her about the idea late last week.

"Organizational continuity and stability is really important, so that's certainly a factor," said O'Toole, who's annual salary will be $150,000.

In a statement issued by MNsure on Wednesday, Benner said that Nyquist is an "outstanding candidate, and the organization is lucky that someone with his background and experience became a finalist for the CEO position."

Also on Wednesday, MNsure said enrollment in private health plans is down slightly over the first 18 days of open enrollment this year compared with 2014.

This year, open enrollment started Nov. 1. Through the first 18 days of the period, including the early morning hours Wednesday, a total of 7,051 people signed up for private coverage through MNsure.

Last year, when open enrollment started on Nov. 15, the count for private plan sign-ups through the first 18 days, including the early morning hours of Dec. 3, was slightly higher at 7,106 people.

O'Toole cautioned against reading too much into the numbers, since the earlier start date for open enrollment this year means people have more time to buy private coverage through MNsure before the first sign-up deadline on Dec. 15.

"We've had good traffic," O'Toole said.

Minnesotans use MNsure to buy private coverage and enroll in public health insurance programs. For most people, private coverage through the exchange is available only during the three-month open enrollment period, whereas people who qualify for public programs can sign-up throughout the year.

MNsure funds its operations by withholding a portion of premiums sold on private plans, so the sale of those insurance policies is key to the health exchange's operating budget. Premiums in the individual market will increase an average of 41 percent next year, so MNsure officials say more Minnesotans will qualify for federal tax credits if they purchase coverage through the exchange.

The numbers released Wednesday suggest that's what's happening.

"About 72 percent of current enrollees are benefiting from tax credits," O'Toole said. "That's up from 55 percent last year. … That's really promising."

Last week, the federal government announced that sign-ups for coverage through the website were up by about 18 percent during first week of open enrollment. The website serves as the health exchange in more than 30 states.

MNsure spokesman Joe Campbell said it's difficult to compare numbers between the state and federal exchanges, because people at certain income levels who buy private coverage through the federal exchange are routed by MNsure into the MinnesotaCare public health insurance program.

MNsure's enrollment numbers as of Nov. 18 show 5,091 sign-ups for MinnesotaCare, compared with 2,954 people who enrolled in the program during the first 18 days of enrollment last year.

"We're seeing a dramatic increase in the number of people on MinnesotaCare this year," Campbell said.

Christopher Snowbeck • 612-673-4744

Twitter: @chrissnowbeck