Marriage equality is spreading across the country — and yet we are in the fight of our lives. While we are opening the doors to opportunity and fairness, people who cling to prejudice and hate are desperately trying to slam them closed. We can’t let them win.

Two weeks ago, Tim and Sean McQuillan celebrated their first wedding anniversary in Iowa. They were the only same-sex couple able to get married in the hours between our trial court victory for marriage equality in Iowa and the temporary hold the court put on that decision while it is under appeal.

In the past six months, thousands of same-sex couples have celebrated joyous weddings in California, and many have traveled to Massachusetts to marry since the discriminatory barrier to out-of state couples was repealed. And in New York, the Governor and the courts ordered state agencies to recognize the marriages of same-sex couples legally married elsewhere.

For years, antigay forces have been using fear tactics and prejudice to persuade voters to pass constitutional amendments to deny marriage equality. I think their time is over.

In California, we are fighting against Prop 8, a pernicious ballot measure that, if passed, would change the California constitution and take away the freedom to marry we just won. There are also anti-marriage-equality constitutional amendments on the ballot in Florida and Arizona.  Wherever we live, we have to help defeat these measures on November 4.

We have been here before. Over half the states have now passed constitutional bans on marriages for same-sex couples, and far more have passed statutes to emphasize their ongoing exclusion of same-sex couples from marriage.

But our world looks different today than it did before – in large part because of the hard work of legal and advocacy organizations, members of LGBT communities and our allies.  We have made the world different  – by winning legal battles, by coming out, by inviting our families and friends to our marriage and commitment ceremonies and by standing up for equality every day at work and in school.

Now we face a moment where we have to fight with everything we have. The antigay industry is pouring millions of dollars into these efforts to turn history back.

Here’s what you can do: Wherever you live, give money as generously as you can to the organizations working to defeat Prop 8 in California and the proposed amendments in Florida and Arizona.  If you live in those states, be sure to register and vote no on Election Day, and talk to as many other voters as you can between now and then. If you can, volunteer your time to canvassing and phone bank efforts to inform others going to the polls of what’s at stake.  And if you live anywhere else, after you make a donation, call anyone you know in California, Florida and Arizona and tell them why equality is so important to you and why you want them to vote against the ballot initiatives.

We have turned a corner and we will not be turned back. Fairness and opportunity are American values. We have to defend them on Election Day.