DENVER (AP) – Saying they are motivated by love, a coalition of religious and family groups have formally kicked off a drive for an amendment to the state constitution that would bar same-sex marriage.

Coloradans for Marriage submitted the proposed wording of the amendment to the Legislative Council office at the state Capitol, the first step toward getting it on the ballot this fall.

The group’s president, Bishop Phillip H. Porter Jr., said the group was acting with “the love of a mother, the gentle guidance of a caring father” to preserve marriage and protect children.

He said the proposed amendment was not about hatred toward gay people.

“We can have it [love]. We are all called to have that love even when it hurts us, even when it hurts others,” said Porter, of All Nations Church of God in Christ in Aurora, a Pentecostal church.

“We live in a nation that wants no pain but all of the gain. We can’t have it both ways,” he said.

However, Lewis Thompson, 59, a retired automotive engineer who lives in Denver with his partner of seven years, views the proposal as a form of discrimination against gay people and a chance for conservatives to get their supporters to the polls in November. In a road atlas, he said he has marked the 19 states that have passed similar amendments and has vowed never to travel to or through them.

“It’s just cementing our second-class citizenship,” said Thompson’s partner, retired teacher and Army reserve colonel Laurin Foxworth, 79, who also attended a press conference called by a group organized to fight the proposed amendment.

Coloradans for Fairness and Equality will also be campaigning in favor of a domestic partnership referendum that Democratic lawmakers want to put on November’s ballot, a measure that would give same-sex couples the same rights under state law as married couples. The group says that same-sex couples are discriminated against because they can’t automatically transfer property to their partners or have them make important medical decisions for them as married couples can.

A third proposal from Sen. Shawn Mitchell, R-Broomfield, would give less rights to same-sex couples than the Democratic proposal but would apply to any other two adults who live together but aren’t married. That could include everyone from roommates to mothers and daughters living in the same household, but gay rights advocates say it doesn’t go far enough.

The coalition pushing the marriage amendment had considered outlawing civil unions but ultimately decided against it. The proposed amendment reads, “Only a union of one man and one woman shall be valid or recognized as a marriage in this state” and that would not conflict with the domestic partnership proposal, executive director Jon Paul said.

“That’s just not our battle. Our focus is on the definition of marriage,” Paul said.

Coloradans for Marriage includes churches, the Rocky Mountain Family Council and national groups such as Focus on the Family, the U.S. Conference of Catholic Bishops and the National Association of Evangelicals, headed by Ted Haggard, pastor of Colorado Springs’ New Life Church.

The group will need approval of the wording from the secretary of state and 68,000 valid signatures of registered voters to get the measure on the ballot.