ANNAPOLIS -- A Maryland resident could register and vote on the same day during the early voting period of a general election under a bill given preliminary approval by the state Senate on Thursday.

The measure would create more early voting centers, increase the number of early voting days from six to eight and expand absentee voting.

The bill was proposed as part of Gov. Martin O'Malley's 2013 legislative agenda, in response to long waits at early voting centers in the November election. Maryland began allowing early voting in 2008.

The provision allowing Marylanders to register to vote and cast their ballot on the same day drew concern from Republicans who worried it would open the system to fraud.

Sen. Allan Kittleman, R-Carroll and Howard counties, offered an amendment that would require people who register and vote on the same day to cast a provisional ballot. Provisional ballots are typically counted about a week after an election is held.

He said Maryland's requirement that voters need to show only a utility bill and not a photo ID to register would lead to fraud.

"I could pick up a Baltimore Gas & Electric bill from my aunt, my uncle's house and say that's who I am, and they wouldn't have any idea if I wasn't my uncle," Kittleman said.

"If someone is waiting until the last day to go register to vote, we owe it to the rest of the citizens of our state to make sure that person is who they say they are."

Kittleman's amendment failed 29-18.

The Senate did, however, approve two amendments. One would allow large rural counties of at least 400 square miles to set up an extra early voting site to cut down on travel time for residents.

The other would require the State Board of Elections to study why voting lines were so long in the 2012 primary and general elections and make recommendations on how to reduce waits.

Sen. Richard Madaleno Jr., D-Montgomery County, worried that such a study -- which is due by the end of this year -- would further delay the implementation of a new voting system scheduled for 2016. Maryland's aging voting system can't be maintained much longer and would be unable to perform a recount.

The bill could be voted on as early as Friday. If passed, it would go to the House.