CHICAGO — The Chicago Cubs, which waited decades to install lights at Wrigley Field and has waited more than a century to win a World Series, took a giant step toward ending the wait for something every other team in the majors already has: a Jumbotron.

The city's landmarks commission, which must sign off on such plans because Wrigley is a city landmark, approved a plan Thursday to allow the team to build a first-ever electronic Jumbotron and other sign above the ivy-covered outfield walls. It did so despite objections from the local alderman, who said the signs would harm the quality of life in the neighborhood, and rooftop owners, who complained the signs will cut into their views and devastate their businesses.

The full City Council still must give its approval. Traditionally in such zoning and development issues, the other aldermen vote the way the local alderman wants. But the tradition of doing what the mayor wants is even stronger, and Mayor Rahm Emanuel clearly wants this deal to go through.

In addition, the decision might have moved the Cubs and the city a step closer to a courtroom. The rooftop owners stopped short of threatening a lawsuit, as they have done in the past, but during the hearing they talked about the tens of millions of dollars they invested in their businesses after signing their own revenue-sharing deal with the Cubs.

"They call it a see-through sign," rooftop owner Mark Schlenker said of the planned sign in right field. "I call it bankruptcy."

For his part, Ald. Tom Tunney focused on what the Jumbotron in left field would do to the neighborhood and asked the commission to imagine what a Jumbotron that is far bigger than the iconic scoreboard in center field would mean to residents right across the street.

The deal would allow the Cubs to erect a 5,700-square-foot Jumbotron in left field of the 99-year-old ball park and a 650-square-foot sign in right field.

"The Cubs often point to large signs at Fenway and U.S. Cellular. Those signs back up to expressways, not people's homes," he said.

And he said the effects of the signs would be felt farther away.

"From blocks and blocks away, the light from the proposed ... Jumbotron will flicker in living rooms and bedrooms throughout the ward," he said. He asked that the size of the Jumbotron be reduced.

The signs have long been the most contentious piece of a $500 million renovation puzzle the Cubs have been trying to put together since the Ricketts family bought the team in 2009.

The Cubs have said that they need the advertising revenue the signs will generate to help fund the renovation project that the team is paying for without public money. Team Chairman Tom Ricketts even suggested in May that he would move the team out of the iconic ball park if he couldn't build the kind of signs the team wants.

Throughout the hearing, the talk was about what the Cubs mean to the city, the fans and residents of what is commonly known as Wrigleyville. Even the commissioners expressed concern that the Cubs were risking changing the ballpark so much that fans would turn away.

"You know you don't appreciate what you have until it's gone sometimes," Commissioner Mary Ann Smith said.

But Michael Lufrano, the Cubs' executive vice president for community affairs, said the team's owners have the biggest incentive of all to make sure fans continue to visit the park.

"We don't want to change it so people won't come," he said.

Emanuel said he is pleased that another step has been taken so that the Cubs can modernize Wrigley Field and the surrounding neighborhood has the investments it needs.

"We committed to a framework of an agreement, and today puts all parties one step closer to achieving the goals set forth in that framework," he said.

Thursday's hearing underlines the fact that Wrigley, famous for the storied billy goat curse and Babe Ruth's called home run shot, is unlike any stadium in the United States.

In fact all the emotion about Wrigley was on display during the hearing that lasted nearly six hours. Supporters of the new signs echoed what Cubs officials have said: That the advertising revenues generated by the signs will help the team win and keep them from abandoning Wrigley Field.

"If the Cubs moved out of the city, it will devastate Wrigleyville," said Cecil Bernard, a neighborhood resident.

But others scoffed at the notion the signs would help turn the Cubs into winners, noting similar talk surfaced before the Cubs erected lights at Wrigley in 1988. They also told the commissioners the changes threatened a singular live sports experience shared by generations of fans.

If the City Council approves the signs, the beginning of the major renovation project could begin as early as later this year. And if the signs do go up, everyone will be watching what they do to the views from the rooftops, where owner charge people to watch the games from bleachers built atop the buildings. The team is in the middle of a 20-year revenue-sharing agreement that calls for the rooftop owners to hand over to the Cubs 17 percent of their gross annual revenue.

Cutting into their views, say the owners, amounts to a violation of their contracts with the team.

The Cubs have said the signs would have a minimal impact on the rooftops and that the views would be "largely preserved." They have pointed out that the massive left-field Jumbotron is in front of one of the few buildings that does not have rooftop bleachers.

At the same time, they've made it clear that minimal impact does not mean no impact, and if what they do to improve their business hurts the businesses that peek over their walls, so be it.