Voters are headed to the polls on Tuesday for primary elections that include a crucial Senate race involving the scandal-haunted Graham Platner.

In Maine, Platner is favored to win the Democratic primary after his main opponent, former governor Janet Mills suspended her campaign. Incumbent senator Susan Collins remains safely at the top of the Republican ticket – just slightly behind newcomer Platner’s lead in polling.

But the oysterman and marine veteran’s string of controversies, ranging from alleged “toxic” behaviour towards women to a tattoo recognised as a Nazi symbol, have plunged Democrats into debates about double standards, purity tests and not letting the perfect be the enemy of the good.

There was a final twist on Monday when Genevieve McDonald, a former political director of Platner’s campaign, published a column denouncing Platner as unfit for office.

“Graham Platner is not someone who would be good for Maine or for the country,” McDonald wrote in the Washington Post. “He exhibits a pattern of dishonest behavior that is impossible to ignore.

“Despite being exposed by a series of scandals beginning last October, he kept assuring voters and the Democratic Party that there were no more skeletons in his closet. Then more emerged – the latest, in recent days, have involved former girlfriends’ serious accusations of physical mistreatment.”

Even so, all the signs on the ground are that most Democratic voters are sticking with Platner, and he has some vocal supporters.

At a campaign event on Sunday, a supporter presented him with a hand-drawn card that included the message “we’ve got your back”.

At the Cross Insurance Center building in Bangor, Maine, on Tuesday women represented both sides of the argument for Platner.

“I like him,” said Jesenia Soler, 39, who describes herself as a transformational self-love practitioner. “He’s very for the people. That he wants to make it more for people instead of corporations is the biggest thing for me.”

She added: “For me it’s like everyone has shit that they’ve done. It’s human. No one’s perfect. The Nazi tattoo: I know he was a marine and you don’t know everything you tattoo on yourself at the time and then you find out and like, ‘Oh, shit!’ and then there’s regret.

“The issues with the women: well, that’s between him and the women. It’s not my job to judge someone on what they’ve done as long as they’ve changed and moved forward and not kept on the same pattern. That’s the important thing.”

That calculus was shared by Kylie Thorwardson, a 23-year-old clinical intern, who acknowledged: “I am concerned. I very much believe women and also realising that this is very convenient timing for things to come out and holding him accountable if anything does come to play. He doesn’t have my vote for life for sure.”

Thorwardson was impressed by Platner’s outsider status and progressive agenda. “Mainers struggle day to day,” she continued. “There is such a high financial disparity and that is concerning. I do think we need higher taxes. If you’re driving around here, you know the roads aren’t great. We need new blood.”

But Jackie Farrell, an 81-year-old retiree who formerly worked for Catholic charities, voted for Mills, whose campaign is inactive but who remains on the ballot. Asked what troubles her about Platner, she replied with a laugh: “That he’s a Nazi – hello? And the girlfriends. I’m a woman so I understand that part of it.”

Across the board, voters in Maine have an independent streak and are frustrated with do-nothing Washington, said Tim Fullerton, a Democratic strategist born and raised in Maine who is now co-founder and chief executive of Find Out Media.

“The best way to make sure that a Mainer does the opposite of what you want is for somebody from outside of the state to tell them to do something,” he said .

“They like that he’s a bit gruff. He volunteered to serve his country and experienced some damage and people understand it. People up there know him, vouch for him and see him doing the work that is necessary to make up for some past wrongs.”