The animal welfare group that gave hens more room in California is working to increase cage sizes nationally with an unlikely ally — the biggest opponent to the state's successful 2008 voter initiative regulating the conditions for egg production.

A bill in Congress would free the nation's 270 million commercial laying hens from cramped cages and put them in larger ones that give them room to stretch and flap their wings, and areas to scratch, nest and perch.

It's a compromise between the Humane Society of the United States and the United Egg Producers, which is trying to head off voter initiatives in other states that could set a confusing array of standards.

Beef, lamb and pork producers fear the bill could lead to more regulations for them.