Pierre Poilievre, the minister for democratic reform, says the changes will clarify some parts of the bill.
The legislation is designed to ensure that voters outside the country provide identification and proof of citizenship and vote only in the riding where they last resided.
One change would make it easier for an expatriate to get someone to vouch for their last residence.
The existing bill would require them to find someone from the same polling division, a small area with a riding.
The change would allow them to get an attestation from anyone living in the same constituency.
Poilievre, appearing before the procedure and House affairs committee, said the legislation speaks to a general belief of the Harper government.
"We believe that people should provide identification when they vote," he said.
The opposition calls the bill an attempt at suppressing the vote in the wake of the government's controversial Fair Elections Act.
"This is just the 'unfair elections act,' part 2," said New Democrat David Christopherson.
Liberal Kevin Lamoureux said the government appears to be frightened. "It seems the government is paranoid about our elections."
Among other provisions, the bill would also attempt to ensure that non-citizens — an estimated 40,000 of whom are on the national voters registry, according to Elections Canada — are not allowed to cast ballots.
It would authorize the minister of citizenship and immigration to provide the chief electoral officer with the names, gender, birthdates and addresses of non-citizens. Elections Canada could then use that information to remove non-citizens from the voters' list.