The bill would create a national sex offender registry, replacing the state-by-state system now in place. To more closely track offenders, those convicted of sex crimes will have to report their whereabouts in person every month or face a felony charge.
Under current law, offenders usually report annually and failure to report is a misdemeanor.
The bill also authorizes funding for tracking devices on sex offenders.
The National Center for Missing and Exploited Children estimates there are about 550,000 sex offenders in the United States, and about 150,000 have failed to register.
"Sexual predators are monsters, and many use the Internet to hunt our children," Hatch said. "It is high time we started using the Web to hunt the sex offenders."
Elizabeth Smart, whose kidnapping captured national headlines, and her father Ed Smart, were supporters of the bill. She was in Washington in March lobbying for support.
The man prosecutors say kidnapped Smart, Brian David Mitchell, did not have a prior record as a sex offender, and would not have been affected by the legislation.
The House passed a version of the bill in June.
Sen. Edward Kennedy, D-Mass., had blocked passage of the Hatch bill. On Thursday, Kennedy relented and allowed the bill to pass.
Hatch was attending the funeral of his sister who died recently and was not in Washington on Thursday.
The bill now returns to the House for approval.
The legislation makes it a crime for sex offenders not to register with their state and requires states to share information when an offender moves to a new state.
Under the bill:
l Sex offenders would have to register in person instead of by mail.
l States could get money to outfit sex offenders with tracking devices.
l Funds would be provided to create a national database of sex offenders.
Additionally, the legislation would provide enhanced penalties in certain sex crimes, expand the scope of the federal DNA index, add to gang crime penalties, and incorporate child pornography prevention measures backed by Hatch.
