"As a transitional government takes hold in Libya, it should seek to undo the injustice of al-Megrahi's release by returning him to the jail cell where he belongs," Schumer said in a statement.
Romney said he wants "this new government to arrest and extradite the mastermind behind the bombing of Pan Am 103 ... so justice can finally be done."
Several other U.S. and British lawmakers also have called for al-Megrahi's return to in Scotland.
The rebels' National Transitional Council has yet to respond to the demands, CNN said.
Al-Megrahi -- convicted in the bombing of Pan Am Flight 103 over Lockerbie, Scotland, that killed 270 people in 1988 -- was sent to Libya in 2009 because he was said to be suffering from terminal prostate cancer. He has survived for years longer than Scottish authorities were told he might when they decided to release him.