“The pharmaceutical lobby is very savvy,” Representative Ro Khanna, Democrat from California, said earlier this week. “They pick the one or two people they need to block things, on the relevant committees or at the relevant time.”

“It may differ from Congress to Congress,” explained Khanna, who is a member of the Congressional Progressive Caucus. “We try to get 90-95% [of the caucus]. They are focused not on 90% , but the blockers.”

In the current Congress, Big Pharma appears to have zeroed in on Senator Kyrsten Sinema, Democrat from Arizona, as one of their lead obstructionists to help kill or gut the Democrats’ drug pricing plan. In the 2020 election cycle, pharmaceutical political action committees suddenly funneled more money to her than they did the whole six years she served in the US House.

Pharmaceutical companies can charge up to four times as much in the United States for name-brand pharmaceuticals than in other countries, in part because Congress barred Medicare from using its bulk purchasing power to negotiate lower drug prices. President Joe Biden and most Democrats support lifting that prohibition in their reconciliation legislation, a move that would save hundreds of billions of dollars – but Sinema has emerged as the party’s most prominent opponent to the plan.

Her heel turn on drug pricing is a dramatic shift. A one-time progressive activist, Sinema campaigned on lowering drug prices in her 2018 Senate race, and she was still calling on Congress to address rising drug costs as recently as last year, boasting on her Senate website that she was fighting to “ensure life-saving drugs” would be more affordable.

But it’s clear now that the pharmaceutical industry has been courting Sinema for some time. Indeed, in March 2021, as pharmaceutical Pac money was flooding into her campaign coffers, drug lobbyists were already bragging to Beltway reporters that they may have found their lead blocker in Sinema.

Sinema has studiously avoided giving the public any details about where she stands on virtually any of the policy proposals in Democrats’ reconciliation legislation – refusing to speak with activists, reporters, or even other Democratic lawmakers.

We only know Sinema opposes Democrats’ drug pricing plan thanks to a Politico report, which cited anonymous “sources familiar with her thinking”. Sinema reportedly told Biden she opposes the party’s proposal and won’t support a weaker offering from conservative House Democrats either.

With the Senate split 50-50, her opposition imperils the whole endeavor.

It makes sense that Sinema would be reluctant to publicly explain her opposition to Democrats’ drug pricing plan – because she would sound absolutely ridiculous, like a craven hypocrite straight out of Veep.

During her 2018 Democratic primary campaign, Sinema released a direct-to-camera ad noting that her family had struggled with healthcare costs when she was younger. “We need to make healthcare more affordable, with access to the lowest-cost prescriptions, and fix what’s broken in the system,” she said in the ad.

Sinema’s 2018 campaign website featured similar language: “Kyrsten is committed to making sure Arizonans have access to more health care choices, low-cost prescription drugs, and high-quality, dependable coverage. As one of the most independent-minded members of Congress, she’s committed to working with anyone – regardless of party – to get it done.”

In a 2019 Senate hearing on prescription drug prices, Sinema noted, “The issue I hear about most back home is the cost of health care.” She went on to cite several stories from Arizonans who contacted her office about their sky-high drug costs:

There’s a gentleman in Mesa, Arizona, who is lucky enough to be insured. But he has seen the price of his medication, to treat a serious lung condition, increase nearly five times in just one year … He’s looked, but there are no generics available that could offer him any financial relief. A woman from Glendale, Arizona, worries about her husband who has a serious heart condition. But his medication costs more than $500 out-of-pocket for a three-month supply. So he refuses to fill his prescription, because he’s worried about how it would impact their family financially. Another Arizona woman struggles to afford her specialty cancer medication. Even though her medication is a generic, she still has to pay thousands of dollars out-of-pocket. And often spends hours on the phone just to understand the unexpected cost increases, and to research payment assistance options. And this, of course, is unacceptable.

In February last year, Sinema published an op-ed declaring: “Congress must address the cost of prescription drugs. Today, even Arizonans who have insurance sometimes struggle to afford the medicine they need. That’s why I’m pursuing policies to ensure life-saving drugs like EpiPens and insulin are affordable and available to Arizonans, especially our senior citizens.”

But by then, drug industry cash was already starting to flood into Sinema’s campaign account.

In May 2020, Kaiser Health News wrote that Sinema had recently “emerged as a pharma favorite in Congress”, based on the fact that she had become “a leading recipient of pharma campaign cash even though she’s not up for re-election until 2024 and lacks major committee or subcommittee leadership posts”.

According to Kaiser’s pharma contribution tracker, Sinema received $121,000 worth of campaign donations from pharmaceutical company Pacs in 2019 and 2020.

For some context, that’s double the amount of drug company Pac money she received during the 2018 election cycle, when she was on the ballot running for Senate. It’s more cash than she had raised from pharmaceutical company Pacs during her entire congressional career to that point.

Over the course of her career, Sinema has accepted more than $500,000 from executives and Pacs in the pharmaceutical and health products industries, according to data from OpenSecrets.

By March 2021, Big Pharma wasn’t just quietly funneling money to Sinema; the industry was publicly signaling that the senator could be its lead blocker in the fight to prevent the government from negotiating drug prices.

“Drug lobbyists see a potential ally in Democratic Sen Kyrsten Sinema, the Arizona moderate who has shown a willingness to break with her party,” Politico reported at the time.

Then, early last month, a corporate front group called Center Forward bought $600,000 worth of television and radio ads promoting Sinema in Arizona. The ads touted her “independence”, and characterized her as “a bipartisan leader” in the mold of the late Senator John McCain.

As The Daily Poster reported, Center Forward has been heavily bankrolled by Pharmaceutical Research and Manufacturers of America (PhRMA), the powerful Washington drug lobby. Two Center Forward board members lobby for PhRMA, as well as drugmakers Amgen, Bayer, Gilead Sciences, Eli Lilly, Merck, Novartis and Sanofi.

A few days after the ad campaign started, Sinema informed the White House that she opposed the party’s drug pricing plan.

Now, senators are talking behind the scenes about ways they can water down the legislation to appease the drug industry, and a second Democratic holdout – Senator Robert Menendez of New Jersey, a longtime top recipient of drug industry cash – has emerged to help Sinema and Big Pharma block the way.

For his part, Khanna said he has tried to reach out to Sinema. But though she was eagerly making herself available to her business donors opposing the reconciliation bill, she wasn’t interested in talking to the progressive congressman, even though he was one of the lead authors of the Medicare drug pricing bill.

“I’ve never met with her,” he said. ‘I’ve offered. She didn’t want to.”

• David Sirota is a Guardian US columnist and an award-winning investigative journalist. He is an editor-at-large at Jacobin, and the founder of the Daily Poster. He served as Bernie Sanders’ presidential campaign speechwriter

• Andrew Perez is a senior editor at the Daily Poster and a cofounder of the Democratic Policy Center

• This article was originally published in the Daily Poster, a grassroots-funded investigative news outlet