Former Commerce Secretary Bill Daley is planning to announce on Monday that he is running for mayor, seeking the office once held by his brother and father.

“He’s definitely announcing on Monday,” a spokesman said Friday. “And he is in to win.”

The spokesman then made it even clearer: Daley, he said, is “announcing to run for mayor, not forming an exploratory committee.”

Bill Daley, the youngest son of former Mayor Richard J. Daley and brother of former Mayor Richard M. Daley, has run for office before.

He has chafed at Mayor Rahm Emanuel’s implied criticism of Richard M. Daley’s reign. It reached a boiling point in April after Emanuel blamed the former mayor, without naming him, for all the tax increases needed to solve Chicago’s $36 billion pension crisis.

In an interview with Sun-Times City Hall reporter Fran Spielman at the time, Bill Daley said it’s “tough to be in politics today” and that he “appreciates the difficulty of the job” Emanuel has to do.

But he said that doesn’t excuse disrespecting his brother.

“I watched my brother for 22 years and my dad for 21 years deal with issues in a tough way,” Bill Daley said. “But, seven years in, I don’t think my dad was blaming Mayor [Martin] Kennelly. And Rich, seven years in, wasn’t blaming Gene Sawyer and Harold Washington.”

Daley has been touted as a potential candidate for governor or U.S. Senate before. The closest he came was in 2013, when he launched a Democratic primary challenge to Gov. Pat Quinn.

He folded the campaign just 98 days after he announced by saying “I’m in this race, OK?”

Political strategist David Axelrod and longtime friend to the Daleys said at the time “He decided it wasn’t what he wanted to do. He didn’t have the fire in the belly.”

William Michael Daley turned 70 in August. In addition to serving as Commerce Secretary under President Bill Clinton, he was chief of staff to President Barack Obama, succeeding Emanuel as the president’s chief gatekeeper.

Bill Daley left the Clinton administration to serve as chairman of then-Vice President Al Gore’s presidential campaign. It was Bill Daley who shocked the nation on Election Night 2000 by announcing that Gore was withdrawing his concession to Republican George W. Bush, saying “This race is simply too close to call.”

Political scientist Dick Simpson of the University of Illinois at Chicago has been quoted describing Daley as a “force behind the throne” and “sort of the brains of the family.”

Daley is one of 15 people to announce he’s running for mayor — though it is doubtful all will gather the 12,500 nominating petition signatures required to get on the 2019 ballot. Other high-profile politicians considering a mayoral bid include Cook County Board President Toni Preckwinkle, Cook County Commissioner Jesus “Chuy” Garcia, U.S. Rep. Mike Quigley and Illinois Comptroller Susana Mendoza.

If he wins the race, Bill Daley would put his family in the record books for the most immediate family members ever serving as Chicago mayor. Bill Daley’s father and oldest brother dominated City Hall for a combined 43 years, eight months and 23 days from 1955 until 2011.

Richard J. Daley was sworn in for his first term as mayor on April 20, 1955 and served 21 years and eight months before his death Dec. 20, 1976, at age 74. Richard M. Daley was first sworn in as mayor April 24, 1989, after a special election for a two-year term and served 22 years and 23 days until Rahm Emanuel was sworn in May 16, 2011.

Richard M. Daley broke his father’s record for the city’s longest-serving mayor. Each Daley was elected mayor six times, eclipsing the record set by the father and son team of Carter Harrison III and Carter Harrison IV, each of whom was elected five times in the late 19th and early 20th centuries. Most of the Harrisons’ terms were two years in length.

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