Democrats in Maine and nationally are racing to find a new Senate nominee in the state’s crucial race, with Graham Platner widely expected to drop his bid after a rape allegation that prompted his most prominent backers to abandon him.

If Mr. Platner does withdraw before the Monday deadline, Democrats will need to act quickly: Maine state law would give the party just over two weeks to identify a replacement by July 27. The law does not determine how that process would work, but the options being discussed include a convention or a statewide caucus in late July.

Choosing a new candidate would be politically thorny, with moderates, progressives and Mr. Platner himself jockeying for influence over who is selected. Democrats would also be newly wary about vetting after their tumultuous experience with Mr. Platner. Any new nominee would have to ramp up quickly and raise money fast to take on Senator Susan Collins, a Republican who has long dashed Democrats’ hopes of taking her seat.

Here are some of the names that have been floated, including likely replacement options and more fanciful ones:

The Politicians and Previous Candidates

Troy Jackson, a progressive who served as the president of Maine’s State Senate from 2018 to 2024, is seen as aligned with Mr. Platner’s politics. Mr. Platner himself listed Mr. Jackson as his top pick for governor before the Democratic primary in June, in which Mr. Jackson came in third place. He is a logger from rural Aroostook County in northern Maine, and his father was a logger, too. By Tuesday, he had formed an exploratory committee to signal his interest in running for Senate.

A Democrat who campaigned as an outsider, Dr. Nirav Shah moved to Maine from the Midwest in 2019 to serve as Gov. Janet Mills’s health director. He led the state’s coronavirus response before becoming the principal deputy director of the U.S. Centers for Disease Control and Prevention in 2023 and most recently working as a professor at Colby College in Waterville, Maine. He ran for governor and led by three percentage points in the first round of the primary, but lost to the more progressive Hannah Pingree in the ranked-choice runoff. He said on Tuesday that he was considering entering the Senate race.

Shenna Bellows, elected as Maine’s secretary of state in 2020, broke into the national news in 2023 when she fought to bar Donald J. Trump from Maine’s presidential primary ballot over his role in the Jan. 6, 2021, Capitol riot. A populist in Mr. Platner’s ideological mold, she often spoke on the campaign trail about her upbringing in a working-class family in rural Hancock County. She previously served as executive director of the A.C.L.U. of Maine and as a state senator, and even won the Democratic nomination for the U.S. Senate in 2014, but lost in a landslide to Ms. Collins. She said on Tuesday that she would “seriously consider” entering this year’s race.

Jordan Wood, a progressive who served as chief of staff to former Representative Katie Porter of California, came in third in this year’s competitive Democratic primary for Maine’s Second Congressional District. He ran on a promise to fight corruption in Washington, citing his work as a co-founder of a nonprofit group dedicated to opposing efforts to overturn the 2020 presidential election. He briefly entered the Democratic primary for Senate in Maine before pivoting to the congressional race. On Tuesday, Mr. Wood said that he was in “conversations” about re-entering the Senate race.

Valli Geiger is a registered nurse and a former mayor of Rockland, Maine, who was elected to the State House in 2020. At a news conference this year, she defended Mr. Platner from criticism of his past remarks about women, saying he had undergone a personal transformation and pointing to his support for rape kit legislation, The Maine Wire reported. She is in conversations about potentially joining the race, she told The Times on Wednesday morning.

Representative Jared Golden of Maine was floated as a replacement candidate, but his spokesman told The New York Times on Tuesday night that “if Congressman Golden wanted the nomination, he would have put his name forward many months ago.” A moderate Democrat, Mr. Golden represents a district that President Trump won in the last three presidential elections. He declined to seek re-election this year, citing the mental toll of political incivility and threats against his family.

The Outsiders

Dan Kleban, a co-founder of the Maine Beer Company, a brewery based in Freeport, briefly ran in this year’s primary for Senate before withdrawing. He pointed to his company’s progressive workplace policies and dedication to environmental philanthropy, and spoke about starting the business after he was laid off during the Great Recession.

Born in Lewiston, the actor Patrick Dempsey gained national fame for his role as a surgeon nicknamed “McDreamy” in the popular television drama “Grey’s Anatomy.” While he is an unlikely replacement for Mr. Platner, he has occasionally attended events with politicians like President Joseph R. Biden Jr. He also collaborated with Senator Angus King of Maine, an independent who caucuses with Democrats, on a campaign against proposed cuts to federal Medicaid funding last year.

Heather Cox Richardson, a historian at Boston College who writes a popular left-leaning political newsletter and lives part-time in Maine, has repeatedly come up in social media discussions about a new candidate. But she stomped out the speculation on Wednesday morning. A Senate run “is not going to happen,” she said in an Instagram video, adding that she was not suited for political office.

Photographs by Roy Rochlin/Getty Images for Authors Guild Foundation, Cj Rivera/Invision, and Associated Press, Brianna Soukup/Portland Portland Press Herald, via Getty Images