Marc Elrich speaks at a debate for Democratic candidates for Montgomery County executive in October. (Sarah L. Voisin/The Washington Post)

Democrat Marc Elrich barely had time to celebrate his razor-thin victory in the primary contest to lead Maryland’s largest county before top business leaders threw their support behind a potential independent challenger, saying the left-leaning lawmaker would be hostile to economic growth.

But two Democratic members of the Montgomery County Council, including one who lost to Elrich in the primary, said they would back him in the general election. They warned that a split among Democrats could open the way to a victory by ­Republican nominee Robin Ficker in November.

Elrich, a three-term at-large county council member, was declared the winner over Potomac businessman David Blair by a margin of 80 votes late Sunday, after the final provisional and absentee ballots were counted.

Blair, a first-time candidate, is considering whether to request a recount.

Democratic council member Nancy Floreen (At Large) said she would announce Wednesday whether she will seek the office as a political independent, after filing paperwork for such a candidacy last week.

Montgomery voters have not elected a non-Democrat as county executive since 1974. But Floreen, who has been elected countywide in four council races and says she has never lost an election, could be a formidable opponent.

Elrich, a staunch progressive with strong union backing, said in an interview Monday that his critics have unfairly described him as running on a “let’s not have development platform.”

“If you’re trying to achieve what I want to achieve, then you need to have money,” Elrich said, noting that if he wants to expand early-childhood education, for example, then he will need to increase the county’s commercial tax base.

He said he is contacting business leaders and the Montgomery County Chamber of Commerce in hopes of getting them to support his candidacy.

A spokeswoman for the chamber declined to comment. But top business leaders in the county said they are wary of Elrich, citing his backing from unions and his past support for rent control. Floreen, they say, would be best positioned to foster good development in the county.

“She’s a person the business community has come to rely on,” said Bob Buchanan, chairman of the Montgomery County Economic Development Corp. “In general, Elrich has an image of not being business-friendly or business-savvy.”

Charles K. Nulsen III, president of Washington Property Co., said the business community sees Elrich as “someone who has cast himself as a pro-union, anti-business candidate” who would do little to improve sluggish economic growth.

Former county executive Doug Duncan (D) said he would strongly support Floreen if she runs and predicted that she would have “a solid chance of winning.”

“Elrich is too extreme. . . . Ficker is way out there,” Duncan said.

It is not clear whether Floreen would win similar support from her and Elrich’s colleagues on the council. Council member Roger Berliner (D-Potomac-Bethesda), who also sought the county executive nomination, said he would support Elrich despite their political differences.

“I am a loyal Democrat, and we have seen too many times what happens when our Democratic Party fractures,” Berliner said. “I’m not a fan of the independent bid.”

Council member Tom Hucker (D-Eastern County), who did not endorse a candidate in the primary, also will support Elrich. “It’s time for Democrats to come together and support the candidate, not to cook up an end run around the process. Doing so only helps Robin Ficker,” Hucker said.

Council member George L. Leventhal (D-At Large), who also ran for county executive, said he has “always supported my party’s nominees,” but he stopped short of endorsing Elrich on Monday.

“I’d like to have a conversation with Marc,” Leventhal said. “Obviously we have significant disagreements about some issues.”

Leventhal expressed doubt that Floreen could win in the overwhelmingly Democratic county and suggested that she may have difficulty collecting the thousands of signatures necessary to put her name on the ballot.

He also said he was “not particularly concerned” about the possibility that a three-way race would pave the way for a Republican win. “I think Robin Ficker has a ceiling of about 12 to 15 percent of the vote,” Leventhal said. “I think it’s extremely likely in a general election that the Democratic nominee will win the election in Montgomery County.”

Montgomery County Board of Elections President Jim Shalleck said the board will vote on Floreen’s eligibility to run as an independent during a July 16 meeting — during which they also plan to certify the results of the June 26 primary. Shalleck said Blair has up to three days after results are certified to request a recount, which he would have to finance.

Jared DeMarinis, director of the division of candidacy and campaign finance for the Maryland State Board of Elections, said Monday that the attorney general’s office had recommended that the board accept her filing and said Floreen must meet all requirements — including switching her party affiliation to independent — by the next filing deadline, Aug. 6.

Asked why she was waiting ­until Wednesday to announce her decision, Floreen said: “There are ducks to be gotten in order, issues to be sorted out, decisions to be made. Nothing is final at this point.”

More from PostLocal: