Conservatives will also push for a federal constitutional amendment banning gay marriage sponsored by Rep. Tim Huelskamp (R-Kan.), although its chances are slim to none in the Democratic-run Senate.

Within a couple of years, the skirmishing could move to Arizona, Colorado, Michigan, Montana, Ohio, Pennsylvania, Wisconsin, Wyoming and Virginia, activists say.

Many Republican politicians, meanwhile, are sitting on the fence. Sen. Rob Portman (R-Ohio) has endorsed same-sex marriage, but his spokesman said Friday that he did not plan to participate in a ballot initiative overturning his state’s ban. And while some current New Jersey Republicans have voted in favor of gay marriage, none showed up at Thursday’s rally in Trenton.

“The key to full marriage equality now resides in the hands of Republican leadership and Republican elected officials,” ACLU executive director Anthony Romero said last week.