Washington (CNN)Vermont Sen. Bernie Sanders said he'll decide whether to run for president "very shortly, within a couple of weeks" in an interview with CNN's Wolf Blitzer on Thursday, but admitted fundraising is "absolutely " his biggest challenge.
Bernie Sanders: 2016 decision coming 'very shortly'
But Sanders already sounded like a presidential contender, offering somewhat of a backhanded compliment for the only declared Democrat in the race, former Secretary of State Hillary Clinton.
"I happen to like Hillary Clinton very much," he said. "And she is far preferable to any of the Republican candidates, let's be clear about that."
Sanders, who has emerged as a prominent progressive Clinton antagonist as he contemplates a potential bid, said that the nation needs a "political revolution" of working-class Americans looking to take back control of the government from billionaires.
Can Clinton lead that revolution?
"That's a good question," Sanders said.
"As I said, she's far preferable to the Republican candidates. But the challenge now is to rally millions of Americans to stand up, and people will have to determine whether her past record puts her in that position," he said.
Clinton maintains a huge lead over her potential primary rivals in every survey of the race, but she faces persistent skepticism from progressives who remain wary of her ties to Wall Street and support for the Iraq war, among other issues.
Sanders, an independent, has fashioned himself as a progressive counterweight to the former secretary of state, but he admitted that he faces a challenge in raising the money he'd need to run a credible campaign, as the Clinton campaign is expected to spend billions.
He agreed with Blitzer that he "absolutely" cannot raise that sum.
"It has to be a credible campaign, not just for my ego but because all of the issues that we're talking about," he said, listing a minimum wage hike, climate change and big money in politics.
"All of those issues that millions of people believe in, I've gotta carry that banner, and if I can't run a good campaign, I'm not going to do it."