For Maine Sen. Susan Collins, a lifelong Republican who believes in limited government, funding for pandemic flu preparations didn’t belong in the Obama administration’s economic stimulus plan. She lobbied hard to kill the money, and as one of only three Senate Republicans supporting the package, she had a lot of leverage with an administration desperate to show bipartisan support in a global economic crisis.

President Obama signed the American Recovery and Reinvestment Act of 2009 in February of that year. Two months later, in April, as a new influenza outbreak, H1N1, known as swine flu, got underway, Democrat David Obey, who chaired the House Appropriations committee at the time, took Collins to task:

“Whether or not this influenza strain turns out to have pandemic potential, sooner or later some strain will. We are not prepared today. Let’s hope we don’t need to be.”

Michael Grunwald, whose 2012 book, The New New Deal, tells the story of the massive stimulus legislation that funneled $800 billion into the economy, recently posted the page from his book that underscores Collins’ power in shaping the deal, along with her insistence that money for pandemic preparation was a non-starter in the bill. She was immovable, according to Grunwald’s reporting.

In response to criticism now about Collins’ 2009 vote, her communications director, Annie Clark, pushed back on Twitter, arguing that the pandemic funding did not belong in the stimulus bill since it was not emergency economic assistance. The money was redirected to community health centers, and funds for flu preparedness later passed as part of the regular appropriations process in a June omnibus spending bill that Collins voted for. She had flexed her muscle on that bill as well, initially voting against it in a cloture vote because it failed to spend funds “carefully and effectively.”

At the time, prominent Democrats like Chuck Schumer, now the Senate minority leader, agreed with Collins that the stimulus bill should be narrowly tailored. But when the swine flu outbreak occurred soon after, it was Collins defending her vote, not Schumer, because her position on what should be in the bill was decisive. Democrats needed her vote to reach the 60-vote threshold to avoid a filibuster.

And that vote came back to haunt her, says Willy Ritch with 16 Counties, a nonprofit formed last year in Maine to hold Collins accountable for votes that he claims are out of step with what Maine voters want. He points out that the $870 million she killed in the stimulus package for pandemic preparedness was in addition to the smaller $500 million for pandemic flu research that had been in the pipeline, and that was approved in an omnibus spending bill.

“Senator Collins talks a lot about the power she has in the Senate, but many of us increasingly don’t like what she does with that power,” Ritch told The Daily Beast. “She always seems to have some convoluted explanation or excuse.” He ticks off Collins’ vote to confirm Brett Kavanaugh to the Supreme Court after saying she believed his accuser, Christine Blasey Ford, but thought she was “mixed up” and “mistaken” about her attacker’s identity. She thought President Trump abused the power of his office, but that “the Founders” would not want her to vote to convict him for doing so. “And she voted for pandemic preparedness after she killed it,” he says.

Collins is running for a fifth term in the Senate in the toughest race of her long career. “Her brand is a centrist, a pragmatic legislator who works across the aisle—and that took a hit when she voted to confirm Kavanaugh and when she voted against removing President Trump,” says Jessica Taylor, who monitors Senate races for the nonpartisan Cook Political Report. “Those are seminal moments, and they make it much harder for her to be seen as a pragmatic lawmaker.”

Collins is one of the last of a kind, the lawmaker whose image is based on crossing the aisle and standing up to party doctrine. “In the age of Trump, it is much harder to have any moderate image, and she is a victim of that,” says Taylor. After impeachment, Collins said she felt Trump had learned his lesson. Immediately after, he made it clear he had not.

Voters who once applauded Collins’ thoughtful pragmatism now increasingly see her as having gone to the well once too often, and that when she arrives at her final position, it was the one she was going to take all along.

Her decline in favorability is stunning. In 2016, according to a Morning Consult survey, she was the second most popular senator after Bernie Sanders. In January of this year, a Morning Consult poll tracker found that Collins is now the most unpopular senator, eclipsing Republican leader Mitch McConnell, who had held the position for some time.

Her approval rating, once in the high 60s, has fallen steadily since 2017, according to a graph compiled by Morning Consult. The line showing her disapproval crossed over in the second quarter of 2019 to be the higher number. “There’s a phrase in polling—the trend is not her friend,” says a longtime political observer in Maine. “She keeps ticking down and ticking down.”

The race is a tossup, and for Democrats, it is a key pickup in their quest to regain majority control in the Senate. The likely Democratic challenger, Sara Gideon, speaker of the Maine House of Representatives, is in a dead heat with Collins in a Colby College poll and has a 4 percentage point lead in a Public Policy Polling survey (PDF).

In the PPP poll, Gideon’s favorable rating is 34 percent, her unfavorable rating is 32 percent, and 33 percent say they don’t know enough about her. Collins’ favorable rating in the poll is 33 percent, her unfavorable is 57 percent, and only 6 percent say they don’t know about their four-term senator.

Finally, what Collins said in 2009 and even today matters less than what Trump does now. “The Senate Republicans are inextricably linked to President Trump and how he handles this crisis,” says Taylor with Cook Political. “He gave himself a 10.”

Few would agree with that assessment, and Collins has urged Trump to step back and let the public health officials lead the messaging. But criticizing Trump is tricky business in the best of times. And for Collins, these are the worst of times.