In contrast, just 31,695 people selected plans on the Massachusetts Health Connector during the previous six-monthlong open-enrollment season, which ended in mid-April.
For enrollment to become effective, people who select a plan must pay their first month's premium.
"We are very happy that so many of our members went on the website this weekend and now have health coverage for 2015," said Jean Yang, executive director of the Massachusetts Health Connector.
Another 6,792 individuals and families were found to be eligible for exchange-sold plans. The exchange also said that since Saturday, 4,989 visitors were immediately enrolled in the state's Medicaid program, MassHealth.
Last year's enrollment season was considered a disaster for the state. Its technologically crippled marketplace was unable to enroll a significant number of applicants online, or even determine whether they were eligible for the tax credits that reduce many customers' premiums.
The state earlier this year scrapped that technology platform, built by vendor CGI, and replaced it with one from a company called hCentive. It credited this change for the dramatic turnaround in performance.
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"The website was stable, reliable and it did exactly what we built it to do: serve as a tool to connect Massachusetts residents to the health and economic benefits of [Affordable Care Act] coverage," said Maydad Cohen, special assistant for project delivery to Gov. Deval Patrick.
"Now it's up to us to build on the strong performance of the first two days, make sure every consumer using the site or calling the call centers enjoys the smoothest experience possible, and finish critical IT upgrades scheduled for December," Cohen said.
A notice on the exchange's website on Monday alerted users that "the Health Connector and MassHealth call centers are experiencing a high number of callers right now," and encouraged them to start their applications online.