"It is not something new," Fallin said at a forum sponsored by The Associated Press.

Fallin was initially critical of the $500 million bond issue proposal because it would take money away from other areas of government. On Wednesday, she said $500 million would not be enough to fill the needs of districts.

"I am the governor of this state, but I am also a mother," Fallin said. "Nothing is more important to me than the safety of our children. I'm asking lawmakers in both parties to work with me this session to support a constitutional amendment giving each school district the tools it needs to protect young Oklahomans from tornadoes, shooters and other threats."

She said the funds could be used for things such as bullet-proof glass and metal detectors in addition to shelters.

Dorman, who is termed out and is considering a run for governor, said the measure Fallin is backing is a property tax increase. He predicted that it would not pass the Oklahoma Legislature.

He said the timing of Fallin's announcement was suspect but didn't doubt the issue had been discussed in Fallin's office.