For decades, Major League Baseball’s goofy love affair with chewing tobacco was so passionate that the gooey stuff was stocked by teams in clubhouses as surely as jocks and socks. Nearly all ballplayers had golf-ball-sized cheek bumps, and part of the show was spitting streams of saliva in dugouts from coast to coast.

But now the end may be near.

If a bill introduced Tuesday in the state Capitol becomes law, the use of “smokeless tobacco” will be banned in every baseball venue in the state — from San Jose sandlots to San Francisco’s AT&T Park. They would join minor league parks, which already outlaw it.

“This is all about helping young people. We want to stop youth from being exposed to cancer,” said freshman Assemblyman Tony Thurmond, D-Richmond, author of the bill. “Kids emulate ballplayers. If they see them use it, they will use it as well.”

The legislation was touted Tuesday at news conferences in Sacramento and San Francisco, where leaders of the Campaign for Tobacco-Free Kids took the podium. Their program, called “Knock Tobacco Out of the Park,” included commentary about oral cancer taking down Hall of Famer Tony Gwynn, a retired San Diego Padre, in 2014 at age 54. And now retired Red Sox pitcher Curt Schilling is battling cancer that he openly blames on his longtime chewing habit.

Opio Dupree, Thurmond’s chief of staff, said Tuesday that penalties for violating the proposed ban have not been determined.

As news about the bill flew like foul balls on Tuesday, baseball players at spring training in Arizona had a range of reactions.

Avid dipper Andrew Susac, the San Francisco Giants’ backup catcher, said he wasn’t too pleased.

“I’ll have to quit,” Susac said. But he quickly added, “It would be a good thing for me.

“My mom and my future wife, they’re hassling me all the time to quit,” said Susac, 24, who tries not to chew on the field or in public.

Oakland Athletics pitcher Dan Otero, who doesn’t dip, said, “I think it will be good to deter young players from maybe getting started.”

Major League Baseball said Tuesday in a statement it is in favor of getting rid of smokeless tobacco. “We have sought a ban of its use on-field in discussions with the Major League Baseball Players Association,” the statement said.

In the ’90s, baseball announcer Joe Garagiola led the movement against chewing tobacco by teaming with retired major leaguer Bill Tuttle, who had mouth cancer. The pair traveled to ball parks to show the deformities — the loss of his teeth and gums, his jaw and his right cheekbone — Tuttle suffered from 40 years of chewing. He died in 1998.

While the players association had no response on Tuesday, Matthew Myers, president of the Campaign for Tobacco-Free Kids, said the bill is the start of a national movement by nine national organizations.

“California seemed like the logical place to start this effort. It has the most teams in baseball. But it’s also important because of the death of Tony Gwynn,” Myers said. “He just meant so much to baseball and California, and he made it very clear before he died that he didn’t want another generation of young people to follow him in using smokeless tobacco. We hope California can be a catalyst.”

Thurmond, elected in November, said he has devoted his life to protecting youth.

“My mom died from cancer when I was 6 years old,” he said.

Meanwhile, at spring training, Giants pitcher Tim Hudson, a non-chewer, predicted a number of players will not go down easily and will test the limits of the regulations.

“It all depends on what the fines and penalties are going to be,” Hudson said. “Guys have habits and are pretty stubborn, and they make a lot of money in here. They can pay a lot of whatever fines they want to give them. That’s going to be the biggest challenge — catching guys. Guys are sneaky.”

Staff writers Carl Steward, John Hickey and Mark Emmons contributed to this report. Contact David E. Early at 408-920-5836. Follow him at Twitter.com/DavidEarlySr.