“If the small businesses’ fears are reasonable, then it could mean that the small business sector grows slower than what economic conditions otherwise would indicate. And small businesses have been a growth engine in the economy,” Friedman told CNBC.

Forty-one percent of the businesses surveyed have frozen hiring because of the health-care law known as Obamacare. And almost one-fifth—19 percent— answered “yes” when asked if they had “reduced the number of employees you have in your business as a specific result of the Affordable Care Act.”

The poll was taken by 603 owners whose businesses have under $20 million in annual sales.

Another 38 percent of the small business owners said they “have pulled back on their plans to grow their business” because of Obamacare.