Source: Heathcare.gov

And you thought Obamacare wasn't popular. Launched Tuesday, the long-awaited online state insurance exchanges were promptly swarmed by millions of people looking to check out prices and sign up for coverage. But the surge temporarily stalled or froze many exchanges, including the Healthcare.gov portal run by the federal government, which is operating exchanges for 36 states. Between midnight and late Tuesday afternoon the website had nearly 3 million visitors, many of whom were greeted by a message saying, "Please wait," rather than being connected to pricing information or an enrollment page. Two million New Yorkers visited the website of their state-run exchange in its first two hours, overwhelming the system. Several state-run exchanges, including Maryland's, delayed opening for several hours, while Hawaii postponed opening for the day. Still, some people were able to enroll, as many more will before the enrollment period ends on March 31. Observers said that what federal officials called the "extraordinary volume" suggested that the government-run exchanges may well be on track to achieving the Affordable Care Act's goal of providing affordable, comprehensive health coverage to 7 million or more people in 2014. The volume came even though recent surveys showed low overall public awareness of the exchanges' existence and operation. (Read more: Obamacare explained)

"They are doing gangbusters," said Chini Krishnan, CEO of the online insurance market GetInsured.com. "They should be very, very happy today. It is awesome news." The exchanges are offering insurance plans at competing prices to the tens of millions of Americans who lack coverage. Many will be eligible for government subsidies to offset the cost. Nearly all Americans must obtain health insurance—either through the exchanges, their employers, Medicare or Medicaid—by 2014 or face a tax penalty. During a call with reporters Tuesday afternoon, Marilyn Tavenner, administrator of Centers for Medicare and Medicaid Services, repeatedly declined to disclose the total number of enrollees or when it would be disclosed. (Read more: Obamacare exchanges: CNBC explains)

"We're not releasing that information yet," Tavenner said. But CMS Policy Director Chiquita Brooks-Lasure said, "We are certainly very pleased with the remarkable interest we have received."

How Twitter covered the Obamacare exchanges launch

President Barack Obama also cited the visitor volume in an address in the White House's Rose Garden, where he was joined by people who he said would benefit from the plans being offered on the exchanges. He also blasted Republicans in the House of Representatives for forcing a federal government shutdown over demands that he and Senate Democrats postpone by one year the mandate that individuals obtain insurance. "Now, like every law, every new product rollout, there are going to be glitches in the sign-up process along the way that we will fix," Obama said. "Consider that just a couple of weeks ago, Apple rolled out a new mobile operating system. And within days, they found a glitch so they fixed it. I don't remember anyone suggesting Apple should stop selling iPhones or iPads—or threatening to shut down the company if they didn't. "As long as I am president, I will not give in to reckless demands by some in the Republican Party to deny affordable health insurance to millions of hard-working Americans," Obama said. Blue Cross/Blue Shield of Florida is selling insurance in all 67 counties in the state through the federal exchange. "We're definitely seeing a lot of volume, which indicates a fair amount of interest going on," said Florida Blue CEO Patrick Geraghty. In addition, he said, phone traffic was "up about 20 percent" during the rollout. While it was hard to know for sure how many visitors to the exchange website would become customers, Florida Blue expects the number of customers to grow from the current 300,000 to between 375,000 and 400,000 during the enrollment period, he said. (Read more: Obamacare deadlines)

Source: Heathcare.gov