More employers think last week's Supreme Court ruling upholding Obamacare subsidies will have a positive rather than negative impact on their business, according to a new poll released Thursday.

The consulting firm Mercer polled nearly 600 employers and found 29 percent believe the ruling issued last week will have a positive impact, compared to 17 percent who think the opposite. Still, most companies, 54 percent, said they don't believe the ruling affects them one way or another.

The firm got responses from companies with fewer than 500 employees (24 percent), 500 to 4,999 employees (47 percent) and 5,000 or more employees (29 percent).

Mercer found that the larger the employer, the more likely they are to see the ruling in a positive light. For instance, 41 percent of companies with 5,000 or more employees thought the ruling was a positive.

"Those favoring the ruling may see advantages to having part-time employees (those averaging less than 30 hours a week) or early retirees obtain their coverage from the public exchanges," Mercer said.

The companies who believe it will have a negative impact might have concerns about whether their employees can access healthcare providers as Americans gain more insurance, the consulting firm added.

The court voted 6-3 that the Obama administration could dole out subsidies to residents in all states, not just states that set up their own exchanges. If the court had ruled the other way, it would have eliminated subsidies for about 6.5 million people.

Employers are set to play a greater role in the healthcare law as the employer mandate goes into effect for smaller businesses next year. For businesses with 50 or more full-time employees, they must provide coverage for 95 percent of their employees.

Businesses with 100 or more employees already had to do this starting this year.

Some employers and opponents of the law say the mandate will require businesses to reduce hours or staff to avoid penalties for not providing costly insurance.