CHICAGO (AP) — Some Chicago-area black clergy amped up opposition to a measure that would legalize same-sex marriage in Illinois, airing radio ads and "robo-calling" residents in black communities urging them to ask their representatives to vote against the bill.

The state Senate last month approved legislation allowing same-sex couples to marry; it awaits a floor vote in the House, where Speaker Michael Madigan has said passing it will be "very difficult."

A new group called the African American Clergy Coalition said it began airing 60-second commercials Tuesday on black radio stations and also plans a "street campaign" to supplement the telephone campaign. The phone messages feature the voice of former state Sen. James Meeks, who is senior pastor of Chicago's Salem Baptist Church.