Progressive activist: Sanders 'at his best when he's an angry old man'

Progressive activist Kyle Kulinski said Wednesday that 2020 presidential candidate Sen. Bernie SandersBernie SandersRahm Emanuel: Bloomberg, Patrick entering race will allow Democrats to have 'ideas primary' Feehery: Pivoting to infrastructure could help heal post-impeachment wounds Jayapal hits back at Biden on marijuana 'prohibition' MORE (I-Vt.) is actually "at his best" when he shows off his famous grumpy side.

“Bernie — in my opinion — he's at his best when he’s an angry, old man because we all relate to that,” Kulinski, a co-founder of progressive political action committee Justice Democrats, told Hill.TV.

“People are mad, people are angry,” he added, citing the growing student debt crisis and current state of health care system. “We want somebody to reflect that — to reflect the dire situation that we’re in, and he by far, in a way, is most like that.”

Asked in an interview earlier this month to name a common misconception about himself, the Vermont senator joked that "there are some times" when he's actually not grumpy.

"They think I’m grumpy all of the time, and I’m only grumpy most of the time," Sanders said with a grin.

Sanders, who ranks among the top five White House contenders in most national polls, is one of the most progressive candidates seeking the Democratic presidential nomination.

In June, Sanders introduced a plan to cancel $1.6 trillion in outstanding student debt.

The legislation, which is being co-sponsored by Democratic Reps. Illhan Omar (Minn.) and Pramila JayapalPramila JayapalJayapal hits back at Biden on marijuana 'prohibition' Progressive House Democrat unveils bill to allow state-based 'Medicare for All' Progressives press Democrats to rethink Israel policy MORE (Wash.), also calls for public universities, community colleges and trade schools to become tuition-free. His main progressive rival, Sen. Elizabeth WarrenElizabeth Ann WarrenRahm Emanuel: Bloomberg, Patrick entering race will allow Democrats to have 'ideas primary' Feehery: Pivoting to infrastructure could help heal post-impeachment wounds Jayapal hits back at Biden on marijuana 'prohibition' MORE (D-Mass.), previously introduced a similar plan.

He has also long championed “Medicare for All,” a government-run system that would effectively eliminate private health insurance.

Sanders’s support for Medicare for All has become a subject of much debate within the Democratic Party.

Former Vice President Joe BidenJoe BidenMost Americans break with Trump on Ukraine, but just 45 percent think he should be removed: poll Democrats release two new transcripts ahead of next public impeachment hearings Press: Ukraine's not the only outrage MORE, who is running on protecting ObamaCare, has expressed concerns about the plan, saying it could result in a lapse in coverage for millions of Americans and possibly leave those with serious health conditions in limbo. Sanders hit back, saying these claims were "preposterous," sparking a heated back-and-forth. 

Kulinski's comments come as Democratic candidates prepare for next week's second round of debates. 

The two-night debate will air on CNN on July 30 and July 31. Sanders and Warren will be two of the biggest names to appear on the stage on the first night, while rivals Biden and Sen. Kamala HarrisKamala Devi HarrisJayapal hits back at Biden on marijuana 'prohibition' Poll: Biden holds 20-point lead in South Carolina Fox News anchor apologizes for saying Booker dropped out of 2020 race MORE (D-Calif.) will be appearing the following night. 

—Tess Bonn