The U.S. Supreme Court has decided not to hear the first of two appeals by the National Organization for Marriage in its effort to withhold the names of donors who helped fund the 2009 campaign against gay marriage in Maine.

The Washington, D.C.-based organization donated $1.9 million to Stand for Marriage Maine, a political action committee that helped overturn the same-sex marriage law passed by the Legislature in 2009.

The organization has argued that releasing its donor list would stymie free speech and subject donors to harassment.

With Monday’s decision, the justices let stand a ruling by the U.S. 1st Circuit Court of Appeals that upheld Maine election laws as constitutional. The National Organization for Marriage argued that those laws are too vague and too broad.

Maine law says groups that raise or spend more than $5,000 to influence elections must register and disclose their donors.

Still pending is a separate appeal aimed at shielding the organization’s donor list. If it loses that appeal, the National Organization for Marriage could be forced to identify donors who gave more than $100 to Stand For Marriage Maine’s campaign.

James Bopp Jr., the Indiana-based lawyer who is representing the National Organization for Marriage in its dispute with the state, did not return phone calls Monday.

Thomas Knowlton, the Maine assistant attorney general who is handling the case for the state, also could not be reached Monday.

The National Organization for Marriage filed its lawsuit in 2009, claiming that Maine laws violated its constitutional rights to free speech and due process.

Maine defended those laws, saying they are designed to inform voters about who is spending money to influence their votes.

This month, gay-marriage advocates announced that they have gathered more than enough signatures to ask voters in November to make gay marriage legal in Maine.

The Legislature passed a law legalizing same-sex marriage in 2009, but it was overturned in the statewide referendum, 53 percent to 47 percent.

Currently, seven states and the District of Columbia allow gay marriages.

In New England, same-sex couples can marry in Massachusetts, Connecticut, Vermont and New Hampshire.