Despite the prevalence of smokeless tobacco throughout Major League Baseball, the fight against it has been gaining more allies in recent years. Add to that list the city of San Francisco, which is hoping to pass a law banning its use locally.

The city is considering an ordinance that would ban the use of chewing tobacco at all ballparks ranging from the local Little League field to AT&T Park, where the Giants play their home games.

The ban would apply to fans and players alike. If it passes, it could be a bold step forward in severing the association between chewing tobacco and baseball.

"San Francisco will send a simple and strong message," said city supervisor Mark Farrell, according to the Los Angeles Times. "Tobacco use in sports will no longer harm our youth, our health."

Although chewing tobacco is legal, its widespread use has previously pushed MLB to seek a ban in the past. But efforts came up fruitless in collective bargaining between the league and the player's association.

In a statement, MLB said it was in support of the proposed ordinance and hopes it helps push chew out of baseball. Chewing tobacco is already banned in the minor leagues, where such rules do not have to be approved by the player's union.

A number of current and former baseball stars have also taken a more vocal role in opposing the use of smokeless tobacco. Former pitching great Curt Schilling has previously blamed his mouth cancer on his use of chew as a player. The death of Hall of Fame hitter Tony Gwynn, following a long battle with salivary gland cancer, has also been attributed to his chronic use of tobacco.

His son, Tony Gwynn, Jr., said in a recent interview on "Real Sports with Bryant Gumbel" that his father acknowledged later in life that tobacco had been a profoundly bad influence on his life, causing his cancer. His son said he believes his father would support a ban if he were still alive.

The L.A. Times reports that an estimated 30 percent of MLB players currently use smokeless tobacco. If the city of San Francisco gets its way, none of them will be dipping when they come to play the Giants.

And that might also mean a decline in the number of teenagers and young adults who pick up the habit after watching their role models use the drug on a daily basis.

More: Stephen Strasburg Wants To Quit Chewing Tobacco After Gwynn's Death