When the Affordable Care Act was being debated in Congress, most Americans yawned if they even bothered reading the bill's fine print—but technology entrepreneur Sanjay Singh's eyes opened wide when he downloaded the proposed legislation.
As he read the bill closely, one section of it drew Singh's attention. "It talked about individual state exchanges. It talked about a federal data hub," he said.
Now Singh's technology company hCentive is reaping a major windfall—helping build online health insurance exchanges for several states, enabling insurance companies to connect with all 51 government-run exchanges, and moving to exploit the new but potentially large private insurance exchange market.
Singh said the idea of insurance plans battling in an online market for millions of customers sounded like "Expedia for health care."
"How do you build an Expedia for health care?" the CEO of hCentive recalled thinking.
He knew it would require a technology platform, and since opening in 2009 with a handful of employees, Reston, Va.-based hCentive is on track to hire its 500th worker this year.
"The ACA—Obamacare as it has become known—has been the driving force for our inception and growth," said Singh. "If I were to guess, I would say we'd be at maybe 600 [employees] by the end of 2014," he said. The company expects to generate about $35 million in revenue next year.
(Read more: Ignorance of Obamacare threatens its success)
When Singh spoke to CNBC, he and his employees were scrambling to get a slew of work done before Oct. 1—the date when the Obamacare exchanges are set to begin enrolling people in insurance plans that take effect in January.
"Right outside my door there is a reverse counting clock," Singh said.
A married 46-year-old with two kids, Singh had experience with a technology-based start-up before founding hCentive.
He co-founded software services company GlobalLogic in 1999 "in my basement," Singh said.
Fourteen years later, GlobalLogic has more than 7,000 employees.
(Read more: Obamacare quirk: Your insurance costs could go up)
In addition to his tech background, Singh said he has a "deep" interest in public policy issues.
"I just love it," Singh said. "I'm a public policy geek. This is my fantasy football."
Those government-run exchanges, also known as marketplaces, will give uninsured people a place to buy affordable, comprehensive health insurance from a range of competing plans. Many of those people would be eligible for tax credits to offset the cost of the insurance, and would have their incomes verified via the federal data hub.
Singh said the idea of building such a platform was particularly attractive to him because the exchanges were effectively virgin territory.
"You normally want to start a business in a new area," he said. "It levels the playing field for an entrepreneur going against the big companies. ... We got started because we thought exchanges would be a big opportunity."
(Read more: How businesses can prepare for the next Sandy)
"Three, or four, five years from now, down the road, all the systems are going to look very differently from the way they did on day one."
In addition to helping implement the state-run exchanges in New York, Colorado and Kentucky, hCentive recently was awarded a contract to work with Illinois, which plans to run its own exchange in 2015 after letting the federal government operate the exchange there in 2014.
And there is room for hCentive to expand its business of setting up government-run exchanges. That's because some of the 34 states whose exchanges are being run by, or in conjunction with the federal government may end up operating their own exchanges, and hiring companies like hCentive to implement them.
"That's the next wave of business," Singh said.
And after Obama was re-elected last year—effectively killing Republicans' hopes of repealing Obamacare—"demand just went through roof" from insurance companies who needed to connect online with the exchanges, Singh said.
(Read more: Doctors confused, skeptical of Obamacare)
"This year we signed 10 to 12 payers or insurance companies," he said. "As late as today, when were are [close to Oct.1] we are getting requests from payers to help them connect to state exchanges."
The company is also being kept busy by the fact that the federal government has been routinely issuing regulations and updated guidance that relates to the exchanges even as the Oct. 1 deadline gets ever closer. Those announcements often require making changes to the technology and interfaces that Singh's company is implementing.
"CMS changes things on an almost daily basis," he said, referring to the federal Centers for Medicare and Medicaid Services. "We literally spend hours every day listening to CMS conference calls."
Even as Singh and his company work to get set for the open-enrollment date, "we are already talking to states about implementing a 'phase two,' things we could not deliver by Oct. 1."
"Three, or four, five years from now, down the road, all the systems are going to look very differently from the way they did on Day One," he said.
Along with business related to the government-run exchanges, hCentive is expanding into the private exchange market.
Those private exchanges give workers and individuals a broader range of insurance plans than might otherwise be available from traditional benefits plans offered by employers. For now, they are a tiny part of the overall U.S. insurance market, but analysts expect them to grow dramatically as employers try to hold down benefits costs.
Singh said hCentive has positioned itself to take advantage of the private exchange market, "if these exchanges do take off."
"One of our goals is that by 2017, 10 percent of the U.S. population at that time, when they access their health benefits, they will do so leveraging or touching our technology," he said. "Either they will be shopping on our platform, or we will enable that transaction."
—By CNBC's Dan Mangan. Follow him on Twitter