With an Election Day decision looming, Boston Mayor Martin J. Walsh today called a vote to legalize marijuana “the wrong way to go” for the state and warned dozens of new pot shops could open almost immediately in the city of Boston if Question 4 passes Tuesday.

“If this law passes, 48 pot shops can happen in Boston in a very short period of time. There is no zoning in the law, that means there is no zoning regulation,” Walsh told hosts Jaclyn Cashman and Hillary Chabot today on Herald Radio. "The voters in Boston could do something to make some changes over time, but initially you're looking at 48 pot shops, they’ll be able to be placed in every neighborhood in the city.”

Walsh, along with other Bay State leaders including Gov. Charlie Baker and Cardinal Sean O’Malley, has been an outspoken opponent of the ballot bid to legalize marijuana in Massachusetts. Yesterday, the mayor — who has often spoken about his own battle with alcoholism as a young man — said there has never been a ballot question he has opposed more than this one.

“This is the wrong way to go for Massachusetts for so many different reasons,” Walsh said today. “There really hasn't been a good reason why we should legalize a marijuana industry in our state. I don't understand the need for another legal drug, if you will, to clog up the problems we already have with addiction and things like that.”

The mayor, a former state legislator, said it would be “very difficult” for the legislature to change the law if the ballot question were to pass.

Polls have consistently shown the “Yes” vote leading with less than a week to go before Election Day.