ADF lies about "marriage protection" amendments
Preying on these and similar fears, advocates of same-sex "marriage" argue that proposed state marriage amendments will undermine the ability of government and even private entities to grant benefits to unmarried people. This false argument is being used to confuse many people...Same-sex "marriage" advocates argue that eliminating domestic partnerships or other counterfeit marital institutions is hateful and mean spirited, because it will undermine benefits granted to unmarried people. Unfortunately, many people (including some so-called "conservative" politicians) have bought into this fallacious argument.
But the ADF is just lying. They themselves, once such amendments have been passed, have been leading the legal efforts to do exactly that, as they have in Wisconsin (and other similar groups have done in Michigan and Ohio):
Conservative lawmakers in Wisconsin also are seeking to block gay state employees from winning the right to employee partnership benefits. That state's Legislature last month approved sending a constitutional amendment to a statewide vote in November that says "a legal status identical or substantially similar to that of marriage for unmarried individuals shall not be valid or recognized in this state."...
The Wisconsin amendment passed partly in response to a lawsuit filed by several gay state university employees seeking health insurance for their partners. The Legislature also has retained the services of a conservative evangelical law firm, the Arizona-based Alliance Defense Fund (ADF), in an attempt to intervene in the workers' lawsuit...
I suspect what the ADF really meant to say in their blog entry quoted above is that they are OK with domestic partnership benefits for unmarried persons of the opposite sex, but not if they are the same sex.