The Cook County Democratic Party on Friday endorsed J.B. Pritzker for governor in next year’s hotly contested primary — bolstering the billionaire and philanthropist’s status as a frontrunner.

Pritzker vowed to fight for working-class families and strengthen the state’s Democratic Party with a vast network of resources, while businessman Chris Kennedy pledged he’d transform the Democratic Party into the party of “reform,” as the two best-known Democratic candidates appeared before party slatemakers Friday morning.

Though sources had earlier told the Chicago Sun-Times Pritzker was expected to get the endorsement, there were numerous calls during the slating session for an open primary.

In June, Kennedy had asked the party not to make an endorsement. That request was echoed by several other candidates on Friday.

Pritzker, though, showed off the scope of his campaign, touting that he has the best field operations and the best communications and volunteer staff. He also spoke of the 17 unions that have endorsed him.

Pritzker said he’s focused on rebuilding the party, “uniting the Democratic Party and winning up and down the ticket.”

“Now more than ever, we Democrats need to come together to defeat Bruce Rauner, to stand up against Donald Trump,” Pritzker said.

Kennedy, meanwhile, warned of “strategic gentrification” he said is pushing out the poor and people of color. He said he’d work to generate a pipeline out of early education and would address education shortfalls and the state’s property-tax shortfalls.

“We need to be the party of reform, of independent maps of term limits, of campaign finance reform,” Kennedy said, adding elected officials should not have outside business interests that are “adverse” to the interests of those they serve.

Illinois gubernatorial candidate Chris Kennedy

Democratic gubernatorial candidate Chris Kennedy. | Sun-Times files

Kennedy urged the same in June when first speaking to the party — targeting the legal work of Illinois House Speaker Michael  Madigan — the state’s Democratic chairman — and political contributions to Cook County Assessor Joe Berrios, the leader of the Cook County Democratic Party.

Kennedy for months has said he wants it to be made illegal for lawmakers or elected officials to work as property tax attorneys. He’s also in support of barring campaign donations from property tax attorneys.

Kennedy joked of the “backroom” party meetings three months ago at the Erie Cafe and did the same on Friday: “Nobody ever wants to be told who to vote for in the primary. I mean, how many times have you gone to dinner and someone says ‘I’ll order for you.’ Nobody wants that. Even in this great restaurant, in the back room of this great restaurant.”

Asked about Kennedy’s critique of the property tax system, Berrios pointed the finger back at Kennedy.

“Number One, I’m not going to get into a fight with Chris Kennedy about property tax appeals. He has properties. You should ask him. Does he appeal them? I’ll leave it that,” Berrios said, referring to Kennedy having used attorneys to appeal property taxes as both a businessman and homeowner.

State Sen. Daniel Biss, D-Evanston, pushed for an open primary and inclusiveness of the Democratic party. He urged city ward and suburban township committeemen to tap into a resource of activists who are trying to “fight back about the tragic governance of Donald Trump and Bruce Rauner.”

Ald. Ameya Pawar. | Sun-Times files

Chicago Ald. Ameya Pawar said Rauner will run a “nasty, racist, bigoted campaign.” Pawar said the Democratic Party should instead run a positive campaign to unite the state. He said he’d announce a running mate within days.

Eight candidates spoke before the party slatemakers on Friday, including Robert Marshall, a physician from Burr Ridge who said he’d want the state divided into four separate states and pushed for the legalization of marijuana.

Marshall, who announced his run for governor at the event, has unsuccessfully sought a variety of offices as both a Republican and Democrat over the past three decades, including a 1990 campaign for governor and later runs for U.S. Senate and Congress, most recently a failed congressional bid in 2016.

The Illinois Republican Party, led by Rauner, reacted to Pritzker’s endorsement by calling the Cook County Democratic Party the “most crooked organization” in state politics.