Democrats’ hopes of winning back the U.S. Senate most likely run through Maine.  

And they’re pinned on Graham Platner, a U.S. military veteran and oyster farmer who will take on GOP Sen. Susan Collins. 

Collins has represented Maine in the Senate since 1997 and is seeking a sixth term. She has long bucked prevailing political trends as a rare Republican senator from a state that otherwise votes reliably Democratic, but Democrats are aiming to capitalize on voter discontent with President Donald Trump and with the cost of living to unseat her.

But the race, already set to be one of the most competitive and highly-watched in the nation, became even more amid a series of personal scandals and controversies surrounding Platner and comments he made online, as well as recent reporting around past relationships.  

Platner easily won the Democratic primary election Tuesday after his main opponent, Gov. Janet Mills, suspended her campaign in April. Mills, who had been recruited to enter the race by national Democrats, had trailed Platner in the polls and cited fundraising challenges as the reason for dropping out, though her name remained on the ballot. 

Platner, a first-time political candidate running as a member of the working class on a progressive, economic populist message, launched his campaign in August to much national attention and fanfare. Progressive senators, including Bernie Sanders, Elizabeth Warren and Chris Murphy, have endorsed his campaign. 

Platner is running with an anti-war message, much of it drawn from his personal story of suffering from post-traumatic stress disorder (PTSD) and struggling with his mental health after serving four combat tours of duty in Iraq and Afghanistan. Platner, who has served in the U.S. Marines and in the Army, has criticized Collins for voting in favor of the Iraq War. Amid Democrats’ struggles attracting support from men — and especially young men — Platner says he seeks to evoke a “healthy” form of masculinity. 

“It is entirely fine to be a weight-lifting, kettlebell-swinging, gun-owning, kind of rugged guy,” he told The New York Times’ podcast, The Interview. “You can do all of that and see your strengths or see your privilege as things that are to be used specifically to uplift and help other people, not to impose on them.” 

But elements of Platner’s personal history have drawn controversy. Last year, he was revealed to have gotten a tattoo of a skull-and-crossbones symbol adopted by a Nazi paramilitary unit. Platner said he was unaware of the symbol’s associations when he got it in Croatia while serving in the military and has since gotten it covered up. He has also apologized for past social media posts on Reddit, including some in which he appeared to blame survivors of sexual assault in the military, saying his most prolific online posting came at a personal low point.

And in the past two weeks, Platner has come under further scrutiny for his relationships with women. Platner’s wife had internally flagged Platner’s sexually explicit texts with other women as a potential liability at the start of his campaign for Senate, The Wall Street Journal and New York Times reported. Amy Gertner, Platner’s wife, said in a statement to The Times that their marriage is “stronger than ever before” and that she was “deeply hurt” by the former campaign aide she said she confided in. 

And on Thursday, The Times further reported on accounts from some of Platner’s past girlfriends who recounted him displaying sometimes volatile, troubling behavior toward them. Platner acknowledged he was not “a perfect boyfriend” in past relationships, citing his untreated PTSD at the time, but he and his campaign have called the most serious accusations outlined in the article false and “politically motivated.” 

And despite concerns from some Democrats in Washington, Platner and his supporters are moving ahead full steam toward November. Over the weekend, Platner held a rally in Bar Harbor with Rep. Ro Khanna of California, one of his progressive supporters in Congress, and a town hall in Portland, attended by hundreds of supporters. His campaign also said it raised $200,000 in the day after The Times’ story, its best day of fundraising since the days Mills suspended her campaign.

“When hurtful things I said on the internet a decade ago came out into the public, as I shared my personal journey through PTSD and darkness, through accountability and growth, Maine had my back,” Platner told the crowd in Bar Harbor on Friday. “Now, as every piece of that past gets dug up, litigated and weaponized, you have my back. And when politically motivated, serious and false allegations are made against me, Maine, you have my back.” 

Republicans currently control the Senate by a three-seat majority, 53 to 47, and senators serve six-year terms, meaning a third of the Senate is up every election cycle. For Democrats to win back the chamber, they’d need to hold on to every seat they have, including competitive ones in Georgia and Michigan. They also would have to flip four GOP-held seats — in addition to Maine, targets include North Carolina and even more Republican-leaning states such as Ohio, Iowa, Nebraska and Texas.