More than 40 Calif.-based groups are backing a new effort to strike out language in the state constitution that defines marriage between a man and a woman.

The groups – led by Los Angeles-based Love Honor Cherish – filed a new ballot proposal with the State of California Thursday as a first step toward getting a measure that redefines marriage on the November 2010 ballot.

To increase the chances of success, the groups are also proposing language that would bar courts from requiring religious ministers to perform any marriage in violation of their beliefs.

“The refusal to perform a marriage under this provision shall not be the basis for lawsuit or liability, and shall not affect the tax-exempt status of any religious denomination, church or other religious institution,” the proposed language states.

While leaders of the new drive believe they can change the hearts and minds of enough Californians in the next 14 months, the state’s largest gay rights group, Equality California, along with several other established groups, say more work needs to be done before bringing the battle back to the ballot.

Furthermore, with Californians gearing up to elect a new governor next year, the chances of success may be even slimmer as conservatives are expected to turn out in larger numbers.

Despite the challenges, leaders of the new initiative insist that they’ll be ready.

“Prop 8 passed with only 52 percent of the vote,” said John Henning, executive director of Love Honor Cherish, referring the California amendment the defined marriage between a man and a woman. “In the next 14 months, with hard work and inspiration, we can change the small percentage of hearts and minds that we need to win.”

Traditional marriage advocates, meanwhile, say their supporters will be ready to again defend marriage successfully whether it's in 2010 or 2012.

ProtectMarriage.com, a broad-based coalition of California families, community leaders, religious leaders, pro-family organizations and individuals, is working aggressively to "educate the public and to help the public continue to understand the very vital role that marriage plays in our civil society," according to its executive director, Ron Prentice.

"While the other side issues many press releases about their activity, we are quietly but effectively building on our majority in California," he stated recently.

Groups supporting the latest pro-gay marriage effort include Stonewall Democrats/Los Angeles, the Latino Equality Alliance, the Mexican American Bar Association, and the San Diego Alliance for Marriage Equality.