New England suffered through some of the hottest summer months on record this year – and that scorching season has extended to the race for Maine’s hotly contested Senate seat, where Susan Collins is in the political fight of her life.

The race is already shaping up to be one of the costliest and most contentious in the country.

Collins, now in her fourth term, had to know that her pivotal vote to confirm Brett Kavanaugh as the newest Supreme Court justice would place a huge, blinking neon target on her back ahead of her 2020 reelection campaign. But the GOP centrist says she didn’t expect shadowy “dark money” liberal groups to spring up in Maine and start flinging arrows at her more than a year before voters go to the polls.

“I have never had so much money on negative ads spent against me so early,” Collins told Maine public radio on Friday. “It’s approximately $1.5 million in false attack ads on television and the Internet, and it’s just been nonstop, and we don’t know who’s paying for those – we have our suspicions.”

The Collins camp doesn’t have to look too hard to find ties to one of her Democratic opponents in the race. The spokesman for Maine Momentum, the dark-money group that has already earned three Pinocchios from the Washington Post for its ad hitting Collins, had worked as recently as June for Collins’ leading Democratic opponent, Sara Gideon, speaker of Maine’s House of Representatives.

Christopher Glynn served as Gideon’s communication director in the speaker’s office, and before that as a spokesman for the Maine Democratic Party. He now has the same communications director role at the 16 Counties Coalition, a project of Maine Momentum, a nonprofit group that does not have to disclose its donors and calls itself a “grassroots advocacy effort” with representatives from each of the state’s counties.

Contrary to its grassroots claims, Collins argues that the group and its affiliates seemed to sprout up for the sole purpose of attacking her. The ad that earned the Washington Post’s rebuke accuses the centrist Republican of putting federal programs for seniors and retirees in harm’s way while giving big corporations massive tax cuts. It quotes “David,” who says he’s a cancer survivor, calling on viewers to tell Collins to “stop risking” Social Security and Medicare.

Moments later, the ad asserts that Collins voted to give “tax breaks to corporations and then took donations from them.”

The Collins campaign has decried the ad as flat-out wrong, arguing that the longtime lawmaker worked to protect Medicare during the tax debate and tied her vote for the tax-cut package to a deal that included provisions ensuring that Medicare wouldn’t be jeopardized. After a lengthy explanation, the Post confirmed that the ad included “a significant factual error and/or obvious contradictions.”

Team Collins says the senator hasn’t taken money directly from corporations because doing so is illegal, although she does accept money from corporate political action committees, which she reports, as required, on her Federal Election Commission filings.

It’s Gideon and the outside groups that support her who aren’t being transparent about their funding, they counter.

“When the former Democratic aides who are running those ads are asked, ‘Who’s paying your salary?’ They have refused to say,” Collins said in the public radio interview. “I think the people of Maine have a right to know. … Just as I have to disclose all of my contributions to the [Federal Election Commission], I think they should have to disclose the source of where their money is coming from, whether they are for me or against me. But [the ads] have all been against me so far.”

In the months to come, dark-money groups on the right will undoubtedly try to fight fire with fire in the Maine Senate contest. So far, though, it’s liberal groups that are staking out the early advertising game, trying to change Collins’ reputation in the state from a pragmatic voice in the middle to a corporate-controlled Republican who has backed President Trump’s agenda and high court nominees at critical points.

In a year in which New England’s two liberal presidential hopefuls — Sens. Bernie Sanders and Elizabeth Warren --  are embracing the socialist mantle and an anti-Wall Street message, Gideon has tried to distinguish herself from Collins by swearing off corporate PAC money. Collins’ campaign, however, argues that Gideon’s big business bashing is inconsistent with her past.

Her GOP critics also point to a campaign finance violation Gideon admitted to in early August in which her corporate-funded political action committee illegally reimbursed Gideon for thousands of dollars in contributions she made to other Democratic candidates in 2015 and 2016.

Gideon’s campaign said she received incorrect guidance on how to process contributions, but a national campaign finance expert called the violation a “pretty clear-cut straw donor” situation and Republican campaign consultants said that “anyone who runs for office” would know that reimbursing yourself for personal election contributions through a corporate-funded PAC is illegal.

“Sara Gideon is trying to have it both ways,” Collins campaign spokesman Kevin Kelley told RCP. “She says she’s against accepting campaign donations from PACs, yet she built her career on donations from pharmaceutical companies, an oil pipeline company, and many other large, out-of-state corporations.

“She says she wants to take on the ‘rigged system’ in Washington, yet she seems eager to accept help from at least one dark money group who refuses to reveal who is funding them, and is operated by someone who used to work for her,” he added.

Gideon also isn’t hurting when it comes to fundraising from out-of-state sources. She boasts the strongest financial backing from groups connected to national Democrats of all four Democrats vying for the chance to challenge Collins. The other three are lobbyist Betsy Sweet, lawyer Bre Kidman and retired Air Force Gen. Jonathan Treacy.

Last week Gideon traveled to San Francisco for a fundraiser hosted by Andrea Dew Steele, founder of Emerge America, a women’s political recruiting group that played a role in Gideon’s decision to enter the political arena. The event was held at Manny’s, a popular Bay-area event site for Democratic fundraising.

Several years ago when President Obama was in the process of renewing diplomatic ties with Cuba, Dew Steele boasted on her personal Facebook page about sitting down with that island nation’s communist dictator, Fidel Castro, for an eight-hour dinner in 2002. The Facebook post came just months before debilitating sonic attacks directed at U.S. diplomatic staff living and working in Havana.

“All this talk of Cuba today reminds me of my trip to Cuba in 2002 and my (8 hour) dinner with Fidel (and 20 others) pictured below with me on the left,” she wrote. “This is a historic time that we are living through.”

Asked about her out-of-state fundraising hosted by a liberal activist in San Francisco, Gideon spokeswoman Maeve Coyle said it’s Collins who’s taking more money from the Bay-area this cycle “than she has from the entire state of Maine.”

Coyle also said Collins has spent 22 years in the Senate raising millions of dollars from special interests and PACs.

“When Collins has been in a position to get money out of politics, she’s repeatedly voted against measures to fix the system and instead prompted and protected the current system – one that benefits her,” she told RCP.

Coyle, however, did not respond to RCP’s questions about Gideon’s former staffer’s communications role for 16 Counties Coalition.  

Kelley dismissed as “laughable” Coyle’s argument that Gideon has an edge over Collins when it comes to decrying special interest money and standing up for campaign finance reform.  

Collins was an original co-sponsor of the most far-reaching campaign finance reform legislation in decades, the 2002 Bipartisan Campaign Reform Act, commonly known as McCain-Feingold, which prohibited national political parties, federal candidates and officeholders form soliciting soft-money contributions – unlimited funds generally used for party-building activities rather than helping specific candidates.

Gideon’s team, meanwhile, has slammed Collins for voting against the Disclose Act, which required many advocacy groups that speak out about politicians’ records to release the names and identities of their donors. The bill was opposed by several free-speech groups, including the usually liberal-leaning American Civil Liberties Union, which argued the bill “inequitably suppresses only the speech of smaller organizations” while allowing “a few large organizations to preserve the privacy of their donors.”

During her Maine public radio interview, Collins clarified that she supports a “level playing field” and legislation that requires all politically active groups to disclose their donors, “whether you’re on the right or the left or the center.”

“Where’s their money coming from?” she asked. “They obviously have a lot of it.”