Now that Karen Willmus can get health insurance through Obamacare, she plans to quit teaching 9th grade English at the end of the school year.

The 51-year-old found policies on the Colorado state exchange for about $300 a month. That's less than what she's paying now for employer-sponsored coverage and less than half what she paid on the individual market in 2007.

Like Willmus, millions of people could quit their jobs or cut back on their hours in coming years because of Obamacare, according to a recent report from the Congressional Budget Office.

The report found that Obamacare could reduce the labor force by the equivalent of 2.5 million workers by 2024, as many Americans may opt to work less to retain eligibility for Medicaid or subsidies. That sparked a fresh round of criticism that health reform is hurting the economy.

But for some, Obamacare is allowing them to become entrepreneurs or retire a few years early since they'll be able to find affordable individual coverage for the first time.

Instead of eating bonbons on her couch, Willmus plans to start her own business with her teen daughter publishing materials for non-native English speakers and others looking to improve their literacy. She expects to work even more than she does now and hire two or three people.

"I can't afford to go out and buy insurance while trying to start a business," said Willmus, of Colorado Springs, Colo. "Obamacare will allow me to be more comfortable at risking what I own."

Related: Obamacare may prompt people to work less

For others, Obamacare frees them to leave a job before they qualify for Medicare.

Edward Perri's job as a grocery clerk has caused him constant back and knee pain in recent years, but he continued to work because he needed insurance. Obamacare allowed him to retire in December after 39 years, 4 months and 23 days on the job.

His retiring at 57 allowed a more junior employee to move up on the job, said Perri, who is single and lives in Muskegon, Mich. Had Obamacare not existed, he'd either have to try to tough it out until he qualified for Medicare at 65 or pay $500 a month for COBRA coverage.

Instead, he's paying $50 a month for a policy. And, as he sees it, the $450 that he would have sent to an insurance company is going to buy groceries, fix his car and take a vacation with his girlfriend.

"That is money I spend in the local economy, creating and saving jobs," he said.

Others may not retire right away, but Obamacare gives them more options to cut back or venture in another direction.

Craig Mason, 59, said he has felt tied to his job as an engineer at a large defense contractor because he and his wife needed health insurance. A diabetic, he couldn't get affordable coverage on the individual market.

Now, however, he's thinking of leaving his employer in a few years to focus more on his side job, repairing and building guitars and other string instruments. He also wants to spend more time with his three grandchildren.

"I want to try something different," said Mason, a Germantown, Md., resident. "I don't want to be tied to a large corporation. The Affordable Care Act may be just the vehicle to bridge the gap until I'm eligible for Medicare."