An unusual coalition of environmentalists, big business, labor organizations, and consumer advocacy groups is banding together against proposed legislation that would make it harder for the federal government to preempt the states with nationwide standards on the environment and a range of other issues. In an effort to shift political power back to the states, bipartisan coalitions in both the House and Senate are drafting legislation that would give local and state governments broad new powers to challenge federal laws and regulations. Activists fear that the bill would lead to a substantial weakening of environmental and consumer protections. The U.S. Chamber of Commerce also opposes it, arguing that varying state standards that could result from the bill would be more expensive for businesses to meet than uniform national standards.