Credit: Win McNamee/Getty Images

The Obama administration will delay a key part of the president's signature health law, but liberals aren't concerned-at least not publicly.

The U.S. Treasury announced on Tuesday that it will delay by one year implementation of a highly touted requirement in the Affordable Care Act, more commonly known as "Obamacare," that companies who employ more than 50 people must provide health coverage for employees who work over 30 hours a week.

Businesses had protested the provision, and in a post to the Treasury's site, Assistant Treasury Secretary for Tax Policy Mark Mazur wrote that the administration would delay the employer mandate to give companies more time to figure out how to complete the paperwork and deal with the administrative requirements associated with granting coverage to more people.

President Obama has acknowledged that implementing the Affordable Care Act might pose some unforeseen challenges-"When you're implementing a program this large, there will be some glitches. There are going to be some hiccups. But no matter what, every single consumer will be covered by the new benefits and protections under this law permanently," he told reporters during a June 7 press conference-but the view from Democrats on "Obamacare" has largely been rosy.

"Thousands of people have already benefited from what we have done," House Minority Leader Nancy Pelosi said during a panel on the law last July.

Expectedly, the new delay has brought criticism from Republicans who have maintained, all along, that the law is too unwieldy to implement effectively and overly burdensome on employers.

But the liberal groups that pushed hardest for "Obamacare" in 2009 and 2010 said they're okay with the announcement. It's minor, they told ABC News, and the Affordable Care Act will march on regardless.

"Today, despite all of the delay tactics and millions of dollars spent by right-wing extremists, the law is moving forward and the new healthcare markets will be ready to offer high quality, lower cost healthcare coverage to middle-class Americans as of January 1, 2014," the Service Employees International Union (SEIU), a major proponent of the law, said in a written statement. "We cannot lose sight of this goal, especially for working women and men who cannot afford to see a doctor or get the lifesaving prescriptions they need."

"Given that 96 percent of businesses have fewer than 50 employees and are therefore exempt from the employer mandate under the ACA, this decision is hardly sweeping. What doesn't make sense about giving the four percent a little more flexibility and time that they're asking for to figure out how best to cover their employees? Makes sense to us," said Lauren Weiner, spokeswoman for Americans United for Change, a D.C.-based liberal group that coordinates activism with unions and other progressive and environmental organizations.

"This is a delay for one provision of the Affordable Care Act, not a change in course for the law. It doesn't change the reality that Obamacare is moving forward," said Ethan Rome, executive director of Health Care for America Now, a liberal coalition formed for the sole purpose of backing the Affordable Care Act as it made its way through Congress. "Twenty-five million people will get coverage, and all of us will be free from the abuses of the insurance industry. It's clear that the business community is serious about implementation. As usual, the Republicans are cynically using this announcement to hide the fact that they're firmly planted on the side of the insurance companies, not consumers."