The Cubs are building a mountain of victories. The major league record for wins in a season is 116, shared by the 1906 Cubs, who did it in 155 games (there were three ties), and the 2001 Seattle Mariners, who did it in 162. To break it, these Cubs would have to go 92-37, a .713 winning percentage that would be just slightly below their current mark.

It seems far-fetched, and the Cubs already lost some of their depth last month with the season-ending knee injury to left fielder Kyle Schwarber. But the Golden State Warriors just set the wins record for the N.B.A. regular season. Sports fans can dream.

“I am not going to answer any question that mentions the Chicago Cubs and the Golden State Warriors,” said Theo Epstein, the Cubs’ president of baseball operations. “Seriously, it’s absurd. We’ve had a good month. They just set the all-time wins record, and they’re working on back-to-back championships. We haven’t won in 108 years.”

Epstein built two World Series winners with the Boston Red Sox but is too smart to forecast a title this fall for the Cubs. Considering the nature of the sports, a fan of the best basketball team should be more optimistic than the fan of the best baseball team.

“If you do have the most talented basketball team — a dominant collection of talent — you can just about pencil them in for a No. 1 or No. 2 seed and, barring something silly, they’re going to show up in the finals with a chance to win,” Epstein said. “In baseball — in this era and with this playoff format — it just doesn’t work that way. In basketball, you can maybe push your chances to like 65 percent of winning a championship. In baseball, maybe you can push yours to 20 percent. It’s a totally different exercise.”

Yet optimism reigns at Wrigley, making this a rare moment for a team best known for heartbreak. This version of the Cubs — Epstein and Maddon, Bryant and Anthony Rizzo, Jake Arrieta and Jon Lester — has not let anyone down. It is still full of promise, a blend of productive imports and rising young stars. The stands seem full of hope, not dread.