SAN FRANCISCO (KCBS) — A real estate taxation measure on San Francisco’s ballot prompted dueling rallies on the steps of City Hall Monday morning.

Proposition G is a measure that calls for a tax on the total sales price of certain properties sold within five years.

State Senator Mark Leno was in attendance and on their side.

“If we want to discourage smoking we put a tax on tobacco products. If we want to discourage short-term investment, we put a surcharge on the flipping of properties,” Leno said.

Supporters of G were visited by a crowd of unwelcome guests in the form of small property owners who say Prop G is an attack on their housing and their lives. Their leader was Josephine Zhao.

“Every piece of brick in that home has their blood, has their sweat on it. They are not speculators. Look at them. Are they speculators to you?” Zhao asked.

The competing rallies showed how contentious Proposition G is and why it has captured so much attention this election season.

Voters will have to decide on this year’s ballot. Election Day is November 4th.