(CNN) - With two weeks until Election Day, a new poll indicates that Democratic Gov. Martin O'Malley of Maryland holds a five point advantage over his Republican challenger, former Gov. Bob Ehrlich.
According to a Gonzales Research and Marketing Strategies survey released Tuesday, 47 percent of likely voters in Maryland support O'Malley, with 42 percent backing Ehrlich, four percent supporting other candidates and six percent undecided. O'Malley's five point advantage over Ehrlich is within the poll's sampling error.
The survey indicates that O'Malley holds large leads in Maryland's Washington D.C. suburbs and in Baltimore, with Ehrlich holding an advantage in Baltimore's suburbs, western and southern Maryland and the Eastern Shore.
A Washington Post survey conducted in late September indicated that O'Malley had an 11 point lead over Ehrlich. Other recent polls suggested O'Malley held a single point advantage.
O'Malley leads as well in the battle for campaign cash, and has slightly outspent Ehrlich on television ad time, according to figures from Campaign Media Analysis Group. But the Republican Governors Association has spent more than $1.3 million on ad time in support of Ehrlich. The RGA spent half a million dollars last week on ad time in Maryland, down from just over $617,000 the week before.
"Just like candidates are working on multiple speeches right now the party committees are working on multiple media plans – they change every day based on poll numbers," says Evan Tracey, CMAG president and CNN's television advertising consultant.
In 2002, Ehrlich become the first GOP governor of Maryland since Spiro Agnew, but he was defeated in his 2006 re-election bid by O'Malley, who was mayor of Baltimore at the time.
Earlier this month President Barack Obama teamed up with O'Malley at a rally in Bowie, Maryland and former President Clinton joins O'Malley at a campaign event Thursday.
Democrats greatly outnumber Republicans and independents in Maryland, and the key to an O'Malley victory would be to ensure that Democrats go to the polls. That was the logic behind the Obama event with O'Malley, which was held at Bowie State University, the oldest historically black college/university in the state. The school is located in Prince George's County, which has a large African-American population and a heavily Democratic electorate. And the Clinton event will be held in Baltimore, the state's largest city.
The Gonzales Research and Marketing Strategies survey was conducted October 11-16, with 816 registered voters questioned by telephone. The survey's overall sampling error is plus or minus 3.5 percentage points.
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