Some Mainers who participated in a focus group this week say they are only reluctantly throwing their support behind Graham Platner over Janet Mills in the U.S. Senate Democratic primary.

Syracuse University and research firms Engagious and Sago held focus groups with voters from Maine and Michigan on Tuesday; both states are considered to be key battlegrounds for control of the Senate come November. The focus group discussions were covered by NBC News.

Of the 13 participants from the two states who said they planned to vote in the upcoming primary elections, all described themselves as either a moderate or a progressive.

The seven Maine participants (as well as the six from Michigan) said they prefer a Democrat who can beat a Republican over one who vows to stand up to President Donald Trump, NBC News reported.

Recent polling indicates that Platner would have a slightly larger lead in a hypothetical matchup with incumbent Republican Sen. Susan Collins than Mills would. (Brunswick Democrat David Costello is also seeking the Democratic nomination, but he trails badly in both fundraising and polling.)

One Mainer said they would rather back a candidate who they said has a concrete platform beyond being “anti-Trump.” Mills released her policy platform this week.

Another said the candidates’ ages are a factor in their decision to support Platner, 41, over Mills, who is 78 and would be the oldest freshman senator in history.

But multiple participants said Platner’s past social media posts and a tattoo linked to Nazis, which he has since covered up, have made them reluctant to back him.

Recent Mills-endorsed advertisements highlighted some of Platner’s controversial online comments about sexual assault and the skull-and-cross bones tattoo resembling a Nazi image. However, Mills’ campaign dropped those attack ads this week.

One woman, who described herself as a moderate, said she was leaning toward Mills but is now backing Platner, though she remarked, “I don’t trust him completely,” according to NBC News.

Another Mainer said they didn’t fully buy the explanations Platner has given for the posts — including that the military veteran says he was struggling with post-traumatic stress at the time — “but I just need somebody who’s going to win.”

Yet another likely voter said the revelation of the tattoo resembling a Nazi symbol was “the closest I have come” to not supporting Platner in the primary. (Platner has said he didn’t know of the tattoo’s resemblance to the Nazi symbol when he got it while out drinking with fellow Marines nearly two decades ago, and that its association never came up in physical exams conducted by the military.)

That voter said “any other signs of antisemitism” from Platner would be their final straw, according to NBC News.