At a fundraiser in January, Philadelphia Councilman Kenyatta Johnson triumphantly clasped his hands with party boss Bob Brady, surrounded by Mayor Michael Nutter, former Governor Ed Rendell, and mayoral candidate and state Sen. Anthony Hardy Williams.

The message was clear — the city Democratic Party was standing with Johnson in his heated bid for re-election against big bucks developer Ori Feibush. Johnson and Feibush face off in May for the Second District seat.

But electricians' union boss John "Johnny Doc" Dougherty, one of the biggest Democratic campaign donors in Philadelphia politics, apparently didn't get the memo.

A high-level source said Monday that Dougherty reportedly approached Johnson at the St. Patrick's Day Parade and allegedly promised to "do everything he can to defeat him," including putting $1 million into the campaign to defeat him.

Dougherty told Johnson that this was retribution for Johnson's political patron, Anthony Hardy Williams, failing to endorse Dougherty's brother in his State Supreme Court run this year, the source said. That move, in turn, was fueled by Williams' impression that Johnny Doc had "put up" fellow mayoral candidate Jim Kenney against him.

Johnson's campaign confirmed the parade conversation in a statement.

"I've always had a good relationship with John Dougherty and I was just endorsed by the Philadelphia Council AFL-CIO, so I was a little surprised when he approached me at the St. Patrick's Day Parade," Johnson said in an e-mail. "Obviously, this has more to do with the mayor's race and the state Supreme Court race than with my race. Whatever happens, I'm not concerned about it. I'm just going to continue to focus on running my own campaign and delivering results for the Second District."

Dougherty told the Daily News shortly after midnight that Johnson's story is inaccurate.

"This is an utter fabrication," Dougherty said. "Claiming that a proud Irishman would say something like this in the middle of the St. Patrick's Day Parade is laughable. The councilman was actually wearing my scarf in the parade, and got my vote at the AFL-CIO on Friday."

Dougherty's move would not be without precedent. He also supported insurgent City Commissioner Stephanie Singer's successful bid for that office in 2011 as payback for longtime incumbent Marge Tartaglione's reluctance to endorse a Council election bid by Bobby Henon. Henon was backed by Dougherty. However, that was a much lower profile race, paling in comparison to the "$1 million" figure supposedly pledged by the union leader.

State Sen. Anthony Hardy Williams said Monday he was aware of the alleged threat Dougherty made to Johnson.

"John Dougherty has a right to support whoever he chooses to support. I think he's tied to one particular mayoral candidate. That will have an impact upon impressions across the city of Philadelphia," said Williams, after leaving a City Council committee hearing. "Whatever he chooses to do that's his business, I don't have anything to do with that."

Williams added that he was also planning to support a variety of candidates in the upcoming election, and contrasted their backgrounds with those aligned with Dougherty.

"The folks I support will show the diversity of the ticket. They will be people of color, people of different sexual orientations. I don't know what Mr. Dougherty's ticket is going to look like."

Kenney's campaign declined to issue a statement. Local Democratic Party boss and U.S. Bob Brady also declined to comment.

It's still unclear exactly what Dougherty's strategy may be. If, as Johnson said, the union leader was planning to dump a massive amount of financial support into Feibush's already well-funded campaign, he neglected to inform the developer.

Feibush said both the encounter and Dougherty's pledge were "news to me."