ST. PAUL  — The staff at Portico Healthnet was all set to start signing people up for coverage through Minnesota’s new health insurance exchange on Tuesday. Unfortunately, the exchange wasn’t ready for them.

After a delay of several hours so that officials could make sure the state’s new online health insurance marketplace, MNsure, was secure and connected to the federal system, it opened for business.

As exchanges across the country opened Tuesday morning, many experienced problems due to intense demand or technical glitches that prevented users from shopping for health plans. That was the case in the 36 mostly Republican-led states that deferred to the federal government to set up and run their exchanges. But several state-run sites, such as Minnesota’s, also had problems.

Mitch Grussing, a 27-year-old self-employed music teacher from St. Paul, said he was anxious for the new exchange to open so that he could look for a plan better than his current one, which charges high premiums and deductibles.

“I’m really interested in getting coverage through MNsure, but if the rollout is delayed, that doesn’t really bother me because coverage doesn’t start until January. But I am eager to get on there and see what coverage they have available,” Grussing said.