Signs supporting a $15 minimum wage are held up at an inaugural event for new Seattle City Council members, city attorney and may Monday, Jan. 6, 2014, in Seattle. Sawant is a Socialist. (AP Photo/Elaine Thompson)

The Freedom Socialist Party has right-wingbloggers seeing red over a job listing that paid less than the group advocates for a minimum wage.

Earlier this month, the nonprofit posted listings on Craigslist and Indeed to advertise an opening for a part-time web designer. It offered to pay $13 an hour or more, depending on the designer's experience. That's well below the $20 minimum wage the party pushes for in its platform, and lower than the $15 wage it helped pass this year in Seattle. Right-leaning sites promptly seized on what they saw as hypocrisy.

But Doug Barnes, the party's national secretary, told The Huffington Post on Saturday that the group relies heavily on donations from low-wage workers and could not afford to pay much to an inexperienced designer.

"We're practicing what we're preaching in terms of continuing to fight for the minimum wage," Barnes said, making his first public comment on the controversy. "But we can't pay a lot more than $13."

He said the party's revenues would increase if the minimum wage were raised to $20 -- and he'd even prefer $22, at least in Seattle. The city will begin phasing in a $15 minimum wage in April.

"Our donor base would all be affected, and the low-wage workers who support us with $5 to $6 a month would be able to give more," he said. "That would affect our ability to pay higher wages as well."

But Barnes said he removed the $13 starting wage from the Craigslist ad on Friday in response to the online criticism.

"The right-wing attack is very hypocritical," he said. "These are the same people who fought against the minimum wage and support companies like Walmart."