Senator Bernie Sanders has called on Democrats to make “a major course correction” that focuses on fighting for America’s working class and standing up to “powerful corporate interests” because the Democrats’ legislative agenda is stalled and their party faces tough prospects in this November’s elections.

The White House is likely to see his comments as a shot across the bow by the left wing of a party increasingly frustrated at how centrist Democrats have managed to scupper or delay huge chunks of Biden’s domestic policy plans.

In an interview with the Guardian, Sanders called on Joe Biden and the Senate majority leader, Chuck Schumer, to push to hold votes on individual bills that would be a boon to working families, citing extending the child tax credit, cutting prescription drug prices and raising the federal hourly minimum wage to $15.

Such votes would be good policy and good politics, the Vermont senator insisted, saying they would show the Democrats battling for the working class while highlighting Republican opposition to hugely popular policies.

“It is no great secret that the Republican party is winning more and more support from working people,” Sanders said. “It’s not because the Republican party has anything to say to them. It’s because in too many ways the Democratic party has turned its back on the working class.”

Sanders, who ran for the party’s nomination in both 2016 and 2020, losing out in fierce contests to Hillary Clinton and then Biden, is a popular figure on the left of the party. The democratic socialist from Vermont remains influential and has been supportive of Biden during his first year as the party tries to cope with the twin threats of the pandemic and a resurgent and increasingly extremist Republican party.

But his comments appear to reflect a growing discontent and concern with the Biden administration’s direction. “I think it’s absolutely important that we do a major course correction,” Sanders continued. “It’s important that we have the guts to take on the very powerful corporate interests that have an unbelievably powerful hold on the economy of this country.”

The individual bills that Sanders favors might not attract the 60 votes needed to overcome a Republican filibuster, and a defeat on them could embarrass the Democrats. But Sanders, chairman of the Senate budget committee and one of the nation’s most prominent progressive voices, said, “People can understand that you sometimes don’t have the votes. But they can’t understand why we haven’t brought up important legislation that 70 or 80% of the American people support.”

Sanders spoke to the Guardian on 6 January, the same day he issued a statement that the best way to safeguard our democracy is not just to enact legislation that protects voting rights, but to address the concerns of “the vast majority of Americans” for whom “there is a disconnect between the realities of their lives and what goes on in Washington”.

He said millions of Americans were concerned with such “painful realities” as “low wages, dead-end jobs, debt, homelessness, lack of healthcare”. In that statement, he said, many working-class Americans have grown disaffected with the political system because “nothing changes” for them “or, if it does, it’s usually for the worse”.

In the interview, Sanders repeatedly said that Democrats need to demonstrate vigorously and visibly that they’re fighting to improve the lives of working-class Americans. “The truth of the matter is people are going to work, and half of them are living paycheck to paycheck,” Sanders said. “People are struggling with healthcare, with prescription drugs. Young families can’t afford childcare. Older workers are worried to death about retirement.”

Sanders has long been troubled by America’s increasing wealth and income inequality, but he made clear that he thinks it is time for Democrats to take on the ultra-wealthy and powerful corporations – a move he said vast numbers of Americans would support. “They want the wealthy to start paying their fair share of taxes,” he said. “They think it’s absurd that Jeff Bezos and Elon Musk don’t pay a nickel in federal taxes.”

He praised Biden for pushing for improved childcare and extending the child tax credit. But he said it would also be good to “show working people that you are willing to step up and take on the greed of the ruling class in America right now.” He pointed repeatedly to the high prices for prescription drugs as an example of “corporate greed”.

“There is no issue that people care more about than that we pay the highest prices for prescription drugs in the world,’’ he said, adding that the pharmaceutical industry has 1,500 lobbyists in Washington who “tried everything to make sure we don’t lower the cost of pharmaceuticals”.

The senator said: “I think the Democrats are going to have to clear the air and say to the drug companies – and say it loudly – we’re talking about the needs of the working class – and use the expression ‘working class’. The Democrats have to make clear that they’re on the side of the working class and ready to take on the wealthy and powerful. That is not only the right thing to do, but I think it will be the politically right thing to do.”

Last Wednesday evening, Sanders did a nationwide live stream in which he talked with the leaders of three long strikes: Warrior Met Coal in Alabama, Special Metals in West Virginia and the Rich Product Corporation’s Jon Donaire Desserts subsidiary in southern California. Noting that hedge funds or billionaires own large stakes in all three companies, he railed against those companies for offering modest raises or demanding that workers pay far more for health coverage even though the owners’ wealth has soared during the pandemic thanks to the booming stock market.

“These entities, where the people on top have done phenomenally well, are squeezing their workers and lowering the standard of living for workers who are striking,” Sanders said. “It’s unacceptable.”

In December, Sanders went to Battle Creek, Michigan, to support 1,400 Kellogg’s workers who were on strike at cereal factories in that city as well as in Memphis, Tennessee; Omaha, Nebraska; and Lancaster, Pennsylvania. In the interview, Sanders said, “I think the Democratic party has to address the long-simmering debate, which is, Which side are you on? Are we prepared to stand with working families and take on powerful corporate interests?”

Sanders voiced frustration with the lack of progress on Biden’s Build Back Better legislation, which the Democrats sought to enact through budget reconciliation, a process that requires only a simple majority to pass. That effort was slowed by lengthy negotiations with the centrist senators Joe Manchin of West Virginia and Kyrsten Sinema of Arizona – and then blocked when Manchin said he opposed the $2tn package, sparking leftwing fury and deep frustration in the White House.

“We have tried a strategy over the last several months, which has been mostly backdoor negotiations with a handful of senators,” Sanders said. “It hasn’t succeeded on Build Back Better or on voting rights. It has demoralized millions of Americans.”

He called for reviving a robust version of Build Back Better and also called for holding votes on individual parts of that legislation that would help working-class Americans. “We have to bring these things to the floor,” Sanders said. “The vast majority of people in the [Democratic] caucus are willing to fight for good policy.”

Sanders added: “If I were Senator Sinema and a vote came up to lower the outrageously high cost of prescription drugs, I’d think twice if I want to get re-elected in Arizona to vote against that. If I were Mr Manchin and I know that tens of thousands of struggling families in West Virginia benefited from the expansion of the child tax credit, I’d think long and hard before I voted against it.”

Sanders also called for legislation on another issue he has championed: having Medicare provide dental, vision and hearing benefits. “All these issues, they are just not Bernie Sanders standing up and saying this would be a great thing,” he said. “They are issues that are enormously popular, and on every one of them, the Republicans are in opposition. But a lot of people don’t know that because the Republicans haven’t been forced to vote on them.”