Democrats may not control the House of Representatives any more, but Congressman Mark Pocan is not giving up on his legislative agenda. Pocan, a Wisconsin Democrat and the former co-chair of the congressional progressive caucus (CPC), instead focuses on playing “the long game” of policymaking.

Pocan’s commitment to promoting progressive policies will be on display on Wednesday, as he reintroduces the Save Medicare Act. The congressman points to his advocacy for the legislation as just one example of how progressives can keep advancing their ideals in a Republican-controlled House and ensure that Democrats will be ready to act when they regain full control of Congress.

“I’ve been in local, state and federal government. Each time, you can impact more people’s lives, but it takes exponentially longer to get things done,” Pocan told the Guardian. “You’re always in the long game.”

Pocan’s legislative to-do list is extensive. When he chaired the CPC, Pocan called for a new kind of American foreign policy, suggesting that portions of the Pentagon’s budget should be reallocated to other services. He has demanded that the nation’s wealthiest citizens and corporations pay fair taxes to help cover the cost of the climate crisis and increasingly expensive childcare.

He has also been an original co-sponsor of the Medicare for All bill since he joined the House in 2013, and used his perch as CPC co-chair to rally support for a single-payer national health insurance system.

Over his decade in the House, Pocan has seen progressive proposals like Medicare for All gain steam within the Democratic caucus and across the country. If progressives can continue to make the case for such policy changes, Pocan said, then Democrats will be better positioned to regain control of Congress in 2024. Right now, he feels confident that they will.

“I think we can then finally respond to the issues that the public is asking for,” Pocan said. “The more we can build that support and awareness on our issues, the better off we are in two years to make sure that they become a reality.”

Pocan views actions like the reintroduction of the Save Medicare Act as a small step in that years-long effort to build a federal government that better responds to the needs of average Americans. The bill that he will reintroduce on Wednesday is aimed at fortifying the traditional Medicare system, which provides health insurance coverage to older Americans. The Save Medicare Act, which will be introduced by Pocan and fellow progressive members Ro Khanna of California and Jan Schakowsky of Illinois, was originally brought up for consideration late last year, but Democrats failed to pass the legislation before Republicans officially took control of the House last month.

The bill targets Medicare Advantage plans, which Pocan and his allies say have been turned into a cash grab for insurance companies. The program, in which healthcare coverage options from private insurance companies serve as an alternative to traditional Medicare, was initially designed as a cost-cutting measure to encourage insurance companies to provide seniors with healthcare coverage at a competitive price. Nearly half of Medicare-eligible Americans are now enrolled in a Medicare Advantage plan.

But multiple lawsuits have documented how private insurance companies seek to overdiagnose Medicare Advantage enrollees to receive more money from the federal government, according to a recent New York Times analysis. The Times found that eight of the 10 biggest Medicare Advantage providers have submitted inflated bills to the government. Estimates of the cost of Medicare Advantage overbilling in 2020 alone range from $12bn to $25bn.

The wasteful spending infuriates progressives like Pocan, who have campaigned to expand traditional Medicare to include dental, vision and hearing coverage. Congressional Budget Office estimates indicate that the cost of Medicare Advantage overbilling could cover the expense of expanding Medicare.

“This has become an additional profit center for these companies, when that could have actually gone towards enhancing Medicare,” Pocan said. “This is a program that doesn’t benefit most seniors.”

The Save Medicare Act would prohibit insurance companies from using the word “Medicare” in plan titles, helping seniors to distinguish between traditional Medicare and private offerings. The bill would also fine companies who attempt to engage in the marketing practice.

Pocan’s own mother, in her early 90s and not especially mobile, was once unable to receive care because her Medicare Advantage plan required her to travel to a doctor’s office in her local community. Traditional Medicare would have allowed a medical provider to come directly to her assisted living facility.

“Many seniors don’t know the difference between Medicare and Medicare Advantage. They don’t understand that it’s not really the government program they paid into,” Pocan said. “I think a lot of seniors are getting ripped off.”

Pocan acknowledged the many hurdles that the Save Medicare Act will face before it can become law. Private insurance companies have a heavy lobbying presence in Washington. But there could be an opportunity for bipartisan cooperation on the bill, Pocan said – particularly if more seniors like his mother share their stories about the program.

“If we can get public awareness up, I think there’s potential for [bipartisan] buy-in,” Pocan said. “I do think this can transcend partisanship in that so many constituents are affected.”

Even if the Save Medicare Act can make it to Biden’s desk, the bill’s success would be the exception rather than the rule for this session of Congress, Pocan predicted. He said he does not expect House Republicans to be particularly productive when it comes to passing legislation. That impression grew stronger after witnessing the bitter battle over the House speakership last month, which ended with Kevin McCarthy winning the gavel on the 15th ballot following a days-long revolt staged by 20 members of the Republican conference.

“The majority is too small with too many extreme members,” Pocan said of his Republican colleagues. “I think what they’re going to put most of their time and effort into are investigations – imaginary ones and real ones.”

But Pocan argued that congressional progressives can still make the most of the next two years. Although Democrats lost the House in November, progressives actually grew their ranks with the addition of new members like Maxwell Frost of Florida, Greg Casar of Texas and Summer Lee of Pennsylvania. Pocan took the victories of those candidates as an encouraging sign that progressives’ message is resonating with voters across the country.

“The American people agree with us on the issues,” Pocan said. “I think this has been a long-term project that we’re having success on.”

• The headline of this article was amended on 1 February 2023 to correct a misspelling of Mark Pocan’s surname.