After months of mostly one-on-one campaigning, gay marriage supporters are rolling out television advertising, bumper stickers and yard signs as they seek to make Maine the first state to legalize same-sex marriage through a statewide vote. Opponents also are stepping up their efforts.

Hundreds of gay marriage advocates gathered Monday at Portland City Hall to launch a ''Yes on One'' referendum push over the next eight weeks leading to the Nov. 6 election. Mainers United for Marriage will follow up with a $100,000, weeklong television campaign beginning Tuesday.