Opponents of natural gas drilling known as fracking say they are planning a protest at the entrance of the Maryland State House to back a complete ban of the drilling practice.
The protest is scheduled for Thursday. A moratorium already is in place, but it expires in October.
The House passed a ban last week 97-40.
Senate President Thomas V. Mike Miller has expressed support for a moratorium. On Wednesday, he said: "I'm favoring that fracking doesn't take place any time in the near future."
Gov. Larry Hogan hasn't decided whether he would veto a measure banning fracking. Hogan said: "I don't know that one's necessary, but we'll take a look at whatever the legislature decides to do with that."
Opponents cite pollution concerns. Supporters say fracking would create jobs.
