A robocall Tuesday night implying that Gov. Martin O'Malley had won his re-election bid before polls closed and advising voters to "relax" provoked swift condemnation from Democratic officials, who accused Republicans of 11th-hour trickery.
But Republicans denied that they were behind the call, which said that polls indicating a Democratic victory "were correct and we're OK," and told voters that "the only thing left is to watch on TV tonight."
State Republican Party Chairwoman Audrey Scott described the call as a "complete disgrace" in a statement and said, "Whoever is responsible for its content should be prosecuted to the full extent of the law."
Scott said that for the Democrats to pin the blame for the calls on Republicans and former Gov. Robert L. Ehrlich Jr.'s campaign without evidence "is absolutely irresponsible."
Soon after news broke of the calls, Baltimore Mayor Stephanie Rawlings-Blake fired off a statement saying Ehrlich's campaign had reached a new low.
"Sadly, this is the kind of gutter politics that we have come to expect from Bob Ehrlich and the Republican Party," Rawlings-Blake said.
Rick Abbruzzese, O'Malley's campaign spokesman, also blamed Republicans for the call.
"It is unfortunate that they would do something like this," he said. "It has to be politically motivated."
Maryland Attorney General Douglas F. Gansler, a Democrat, announced that he would investigate the calls and prosecute illegal campaign tactics.
Residents reported receiving robocalls from a person who identified himself as Rep. Elijah E. Cummings about the same time as the calls advising voters that O'Malley had won.
In that message, the caller who identified himself as Cummings warned against voter suppression efforts by Republicans and reminded residents that the polls were open until 8, according to those who received the calls.
Attempts to reach Cummings for comment Tuesday night were unsuccessful.
Residents reported receiving the call telling them to "relax" between 6 p.m. and 7:30 p.m. Polls closed at 8.
"I'm calling to let everyone know that Governor O'Malley and President Obama have been successful. Our goals have been met," a female voice said. "Relax, everything is fine. The only thing left is to watch on TV tonight."
John Lundquist, a teacher and Highlandtown resident, said the message was left on his answering machine. "It's just amazing," he said. "Here we are in the 11th hour of the election, and these tactics are still going out. Whoever has paid for this call to go out is depending on voter apathy."
Robert Hillman, 71, a semiretired attorney from North Baltimore, described the call as "strange," particularly because the caller did not identify herself.
Heather Dewar, an editor for the Urbanite Magazine, was one of several residents who said they were confused because they received the Cummings call before the phony O'Malley victory announcement.
Many residents reported receiving the "relax" call from a Washington, D.C., area code number. Attempts to track the number were not immediately successful. A dial tone is heard when the number is called, and no records are listed for it in phone databases.
Complaints on websites regarding past calls from the number link it to calls apparently made on behalf of some Democratic candidates across the nation, including an incumbent governor in Tennessee and a candidate for New York state senate, Susan Savage.
Other online posters reported calls from the number regarding nonpartisan elections, such as a school board race in Florida.
Savage's Republican opponent, Hugh T. Farley, said in a phone interview that the robocalls made against him had been "vicious." He said he never paid for any calls himself, referring to them as "counterproductive."
A call to Savage's campaign headquarters was not immediately returned.
Baltimore Sun reporters Scott Calvert and Jessica Anderson contributed to this article.