WASHINGTON -- The Senate wants to replace a Bush administration program to secure driver's licenses with a plan that would cost states less money.

Homeland Security Secretary Janet Napolitano said the new plan, which was introduced Monday, would refine the current Real ID program, but would not gut the security requirements of the law, passed in 2005 after the Sept. 11 terrorist attacks.

"It is a recognition that Real ID, as originally passed, is simply not being put in place by the states," Napolitano said Monday.

The National Governors Association helped write the new proposal. As Arizona governor, however, Napolitano said the Bush administration did not collaborate enough with governors in the development of the congressionally mandated program. The association said the current law would cost states $4 billion while the new plan could cut the costs to between $1.3 billion and $2 billion, the association's spokeswoman said.

The 2001 attacks were the main motivation for the original law. The hijacker-pilot who flew into the Pentagon, Hani Hanjour, had four driver's licenses and ID cards from three states.

Real ID-compliant driver's licenses have several layers of security features to prevent forgery, such as verification of birth certificates, Social Security numbers and immigration status. Unless the current law is changed, people would need a driver's license that meets the Real ID standards to board an airplane. But the proposed plan would not require that birth certificates be confirmed with the agency that issued them, or mandate that people need these licenses to board planes.

The Bush administration said Real ID would hinder terrorists, con artists and illegal immigrants. Opponents said it will cost too much and weaken privacy protections.

Rep. James Sensenbrenner, R-Wis., said the new proposal would bring the country back to pre-9/11 standards.

"She's dead wrong on this issue," Sensenbrenner said of Napolitano.

Sensenbrenner points to the 9/11 Commission Report which called for a secure driver's license.

According to the commission report, "For terrorists, travel documents are as important as weapons."

"It's pure appearance of security, it's not real security," said Janice Kephart, an expert on travel document security who worked on the 9/11 Commission report.

Sen. Daniel Akaka, a co-sponsor of the bill, said the new proposal does exactly what the 9/11 Commission recommended:

"It sets strong security standards for the issuance of identification cards and driver's licenses," the Hawaii Democrat said in a statement.