Organizing for Action, the nonprofit advocacy group launched this year to back President Obama’s second-term agenda, raised more than $7.7 million in the last quarter, bringing its total  to nearly $21 million.

More than 355,000 donors have given the group $58.50 on average this year, according to a voluntary disclosure that OFA released Friday evening.The group has also scooped up some big checks: More than $3 million has come from 19 wealthy contributors who have contributed six-figure sums, such as Chicago media mogul Fred Eychaner, who gave $500,000, and architect and gay rights activist Jon Stryker, who donated $100,000.

But OFA — which can accept unlimited sums as a nonprofit “social welfare” advocacy group — has not yet pulled in the million-dollar donations that have fueled super PACs and advocacy groups on the right. The group had to scale back its goal to raise $50 million this year after officials reversed their original plan to accept corporate donations amid sharp criticism.

The organization has worked to promote Obama’s efforts to pass immigration reform and gun control measures and has most recently been urging its members to pressure Republican House leaders to pass a spending bill to reopen the government.

On Friday, Jon Carson, OFA’s executive director, urged supporters to tweet at House Speaker John Boehner with the hashtag #EnoughAlready.

“Now is the time to send a strong message on Twitter (and anywhere else you want to drive it home),” he wrote in an eemail.