(Washington, DC) -- Repealing the Defense of Marriage Act and legalizing same-sex marriage nationwide will not be easy. That is the opinion of two Democratic U.S. Senators speaking on CNNs "State of the Union." Senator Debbie Stabenow of Michigan said a patchwork of gay marriage laws around the country makes it difficult for Congress to make such changes. Senator Bob Casey of Pennsylvania said using a constitutional amendment for defining marriage only serves to divide and demonize people.