St. Louis ? Lawmakers in Missouri had the chance, after two buses packed with high school band members slammed into a freeway wreck caused by a teenager who was sending a flurry of text messages, to impose tougher limits on driver cellphone use. It got filibustered.

Federal transportation officials are citing that accident in pushing for states to enact an all-out ban on cellphone use by drivers, restricting the use even of hands-free devices. But spurring lawmakers to take up the cause may be difficult. Skeptical lawmakers give the proposal little chance at succeeding in state capitols around the country, and many aren’t planning on introducing ban bills.

The reason? While acknowledging growing safety concerns, lawmakers are wary of inconveniencing commuters and say a complete ban would be one of the deepest government intrusions yet into the daily lives of motorists who have woven their phones tightly into their daily routines. Others are worried a ban would be unenforceable. And the cellphone legislation in most states already took years to get approved.

“It’s a popular thing to pass another law,” said Bill Stouffer, a Missouri Republican and chairman of the state’s Senate Transportation Committee. “But anything that takes your eyes off the road is just as deadly as texting or talking on the cellphone. Where does it end? Why not ban map reading or eating while driving?”

The centerpiece of the NTSB’s proposal was an August 2010 wreck southwest of St. Louis in which a pickup truck slammed into the back of a semi cab that had slowed for road construction, and the buses then crashed into the wreckage. The pickup driver, Daniel Schatz, 19, and a bus passenger, Jessica Brinker, 15, died. Thirty-eight people, mostly students, were hurt.

Investigators said Schatz had sent and received 11 texts in 11 minutes just before the accident.

The NTSB’s recommendation far exceeds the patchwork, and largely unenforced, prohibitions many states now have. Thirty-five states and the District of Columbia ban texting while driving, while nine states and Washington, D.C., bar handheld cellphone use. Thirty states ban all cellphone use for beginning drivers. No state bans the use of hands-free devices for all drivers.

In Idaho — which has historically resisted federal mandates and is one of seven states without any sort of regulation on the use of cellphones by drivers — proposed bans have been rejected the last two legislative sessions after lawmakers questioned their enforceability and the need for new government dictates. South Dakota has a broader law discouraging “distracted driving” but lawmakers have steadily opposed specific bans on electronic devices.

“I was listening to all this heart-wrenching testimony against texting behind the wheel, and I got to thinking about all the calls I’d gone off to where someone was hurt in a car accident,” said South Dakota Republican Rep. Betty Olson, an emergency medical technician from Prairie City. “In just about all of them, they were distracted, so what they were doing was already against the law,” Olson said. “They wouldn’t be paying any more attention to a law banning texting.”

Driver inconvenience is also among the factors state lawmakers cite in their opposition. Others note that cellphones have benefits. In some parts of rural South Dakota, Olson said, a driver’s cellphone can be “a life saver.”