MADISON, Wis. -- Less than a week after the November election, some officials with the city of Madison and Dane County said that they are scrambling to protect domestic partner benefits in the wake of voters backing a state constitutional amendment to ban gay marriage and civil unions.

Madison Mayor Dave Cieslewicz said that he has asked City Attorney Mike May to look for ways to defend the city's domestic partner benefits in case of a court challenge. Cieslewicz said that currently, no changes are afoot, WISC-TV reported.

"I have not heard of any potential challenges," Cieslewicz said. "But we have asked the city attorney to review it to make sure that our system is as legally defensible as it possibly can be."

Cieslewicz asked the city attorney to research the legal ramifications after the controversial marriage amendment was approved by voters last Tuesday. Wisconsin voters approved the amendment 59 percent to 41 percent.

County officials said that they aren't sure what impact the amendment will have on Dane County domestic partner benefits, but a legal opinion issued by Kriti Gullen, assistant Dane County Corporation counsel, warned that such benefits could face a serious threat if there is a legal challenge.

In the memo issued last December in anticipation of the marriage amendment vote, Gullen wrote:

"I believe that passage of the constitutional amendment would place the domestic partner benefits offered by Dane County at serious risk to legal challenges to the constitutionality of those benefits involving years of litigation."

Both the city and the county offer domestic partner benefits to union and non-union members.

Joanne Haas, assistant to County Executive Kathleen Falk, said that if there is a court challenge to the benefits, the county will argue it negotiated in good faith with several unions to provide domestic partner benefits, WISC-TV reported.

Cieslewicz said that the city will be prepared if a challenge is made.

"We will vigorously fight any attack on our domestic partner benefits," Cieslewicz said.

Cieslewicz said that domestic partner benefits make both moral and economic sense.

"Madison is near to being a full employment economy," he said. "Our sustained unemployment rate is around 3 percent. We can't afford to put out the unwelcome mat to anyone."

County officials said that they're watching the state of Michigan where the state's Supreme Court is due to rule on the impact of its marriage amendment on domestic partner benefits.

The mayor said that city attorney will have a legal opinion on the topic within a week, WISC-TV reported.