The nation's largest union boldly pledged a year ago to rally states to sue the Bush administration over education spending under the No Child Left Behind (search) law.

It turns out that the National Education Association (search) has been the one left behind.

At least 30 state legislatures, including some led by Republicans, have expressed their displeasure over the law. Not one state, however, has agreed to join a lawsuit the teachers' union announced one year ago and planned to file by last summer.

"Maintaining a good relationship with the federal government that oversees your programs and suing them at the same time makes it a very difficult proposition," said Patty Sullivan, deputy executive director of the Council of Chief State School Officers (search).

"You have to be pretty certain that you're going to win, because you really will jeopardize your ability to get other things. You have to think through the politics of that," she said.

The threatened challenge, which would have been the most direct shot at the heart of Bush's domestic agenda, is not dead, the union says. A few school districts have agreed to participate and the union is weighing when to go on if no state joins the fight.

Union leaders claim the primary reason the suit has stalled is that states fear retaliation by the Education Department (search). Yet participation by states is critical because they would have the strongest standing to sue, the union says.

"It's difficult to think that in 2004, there is fear of reprisal, intimidation and harassment," said Reg Weaver, the NEA's president.

Added the group's general counsel, Bob Chanin: "I would have thought they (states) would be jumping at this. We have a solid legal theory. We're prepared to do all the work. We just want to enlist them, but for a variety of reasons we haven't been able to push any state over the hump."

Union leaders could not offer proof of threats against states or name ones that fear retaliation. But they said state and local school officials tell them they fear cuts in discretionary programs, such as reading grants, or rejection of changes they want in state school plans.

Education Department spokeswoman Susan Aspey said the claims were "utterly baseless" and that the administration has proved it works closely with state policy-makers. "We're pleased the states have chosen to work directly with us rather than through the courts," she said.

A lawsuit would hinge on a provision of the law that says states and school districts would not have to use their own money to pay for any of the law's requirements. It is an important issue because debate has been continuous over whether the government is paying enough to implement the law.

The NEA courted a plaintiff from the Democratic Governors Association (search), a group to which the union makes considerable donations through its political committee.

The governors support the NEA but have opted for "rigorous discussions" with the administration about their problems with the law, spokeswoman Nicole Harburger said. She said Democratic governors did not fear reprisal if they were to join the suit.

The law is considered the most sweeping education overhaul in almost 40 years, a bipartisan effort intended to help schools succeed and to punish many that fail.

It demands highly qualified teachers in all core classes, expanded standardized testing, more information for parents and verifiable yearly progress among many subgroups of students.

As the law's effects began to take hold, most states debated or passed measures to seek relief. Vermont and Maine have passed laws prohibiting use of state money to pay for the law's mandates, the same basic ground of the proposed NEA suit.

A few considered opting out of the law, thereby rejecting millions of federal dollars for poor children, although none did. A lawmaker in one such state, Democratic Sen. Steve Kelley of Minnesota, said any fight for money by a state could be portrayed as opposition to the law.

"State legislatures support the idea of closing the learning gap," said Kelley, a leader of a task force on the law for the National Conference of State Legislatures (search). "You would not want to be in a position where somebody on the other side could say that you are suing in order to preserve an inequality of results for kids."

States cited other reasons for staying out of the suit -- internal disputes among crucial personnel or organizations, lack of data about their state's costs, hopes that Congress will change the law.

Meanwhile, the states are feeling heat from below. Half face suits from local agencies over the adequacy of school financing; that may grow as scores emerge about achievement of poor and minority students, reporting required by the new law.

The NEA says just the threat of a suit has been a success, drawing attention to the question of whether Bush has kept his promise about the size of his spending increases.

The 2.7-million member union begins its annual meeting this week in Washington, when it expects to endorse Democratic Sen. John Kerry for president and raise perhaps $1 million for its political committee.