Graham Platner, a 41-year-old oysterman with no prior experience in elected office who has been plagued by scandals since announcing his campaign, won the Democratic primary for U.S. Senate in Maine on Tuesday.

Platner’s victory comes despite months of damaging headlines over his background, including a Nazi-linked tattoo and accusations of abusive behavior in past romantic relationships, which caused deep division within his own party. Reporters also dug up his past comments on sites such as Reddit, which veered into crude and offensive territory.

His win will be seen as a heartening moment for the progressive left, which rallied behind Platner’s opposition to the Israel lobby, AIPAC, and dark money in politics. He’s also a supporter of Medicare for All, a system that would establish single-payer healthcare in the U.S.

But it raises serious fears for the party’s establishment flank. For months, Platner has been beset by negative press and denunciations from figures within the Washington Democratic establishment over a tattoo he got during his military service of a “Totenkopf,” a death’s head or skull and crossbones design that was used as an insignia by Nazi SS members.

Platner has denied knowing the image’s meaning when he got the ink, but the issue has led to condemnations from fellow Democrats, including Rep. Jared Moskowitz and Sen. John Fetterman, and calls for the party to abandon support for his campaign altogether.

A report in The New York Times last week also detailed a pattern of past alleged behavior with girlfriends that was described at times as “unsettling.” The report’s central figure, who dated Platner for two years, detailed a pattern of behavior including incidents in which he would allegedly grab her hard enough to leave marks or held her in a room during arguments while not letting her leave. She said the incidents left her “shaken” and “afraid”; Platner denied that any instances of violence had occurred.

Coupled with the volume of negative headlines surrounding the tattoo scandal, the issues have led to a sort of “scandal fatigue” that was cited by many supporters of Platner leading up to Tuesday’s election as many voters viewed it as a sustained media smear campaign.

He defeated a handful of lesser-known candidates as well as the state’s Gov. Janet Mills, 78, who was recruited to run by Senate Democratic leadership and spurred on by the D.C. consultant class. Mills effectively ended her campaign in late April as polls showed her being roundly trounced by Platner at every turn.

Democrats who remain supportive of Platner through the onslaught of bad press counter that Senate Democratic leadership were ultimately to blame, as they failed to find a more inspiring candidate for the seat — pointing to the oysterman’s continued popularity and the inability of Mills to gain any traction in the race.

Platner heads now into potentially the most-watched Senate race of the cycle. His showdown with Susan Collins represents a major priority for Senate Democrats as they seek the majority this November; the chamber is currently split 53-47. Platner’s victory in Maine is crucial to the Democratic path to a majority next year, a possibility that didn’t seem real just one year ago.

Democrats are already favored in many polls to win back the House by a small margin this cycle. A victory in the Senate would not just halt the Trump administration’s legislative agenda, but open up the possibilities of serious resistance to the president’s priorities — up to, and including impeachment.

The party needs to gain four seats in the upper chamber to secure a full majority, though persisent defections (like John Fetterman) could still hand Republicans some key victories. Aside from Platner, the party is eyeing seats in Alaska, Texas, Ohio and North Carolina all held by Republicans, two of which are in play as a direct result of Donald Trump picking fights with members of his own party.

Platner leads Collins in recent polling, but the race is expected to tighten significantly as Senate Republicans unload a massive war chest to defend Collins, one of their most reliable purple-state members. A five-term senator with a penchant for winning tough races, Collins is 73 and has been been criticized by Platner for supporting Trump’s war with Iran, which according to polls is now supported by only roughly one third of Americans.

Collins’s value to the Senate GOP’s numbers is so pronounced that she has escaped the brunt of Donald Trump’s wrath, even as she broke with the president on multiple votes including his “One Big, Beautiful Bill” last year. The president did not endorse Collins outright, but she did not face a meaningful primary challenge as a result of maintaining his tacit support. Other senators who did the same, or less, were not so lucky. Trump endorsed against two incumbent GOP senators this cycle who both lost their respective primaries.

He likely would have done the same in North Carolina had Sen. Thom Tillis not elected to retire instead.