Paul E. Schurick, the 2010 campaign manager for former Maryland governor Robert L. Ehrlich Jr., was convicted Tuesday by a Baltimore jury of four counts stemming from a robocall that prosecutors said was intended to suppress the black vote.

The call, which Schurick acknowledged authorizing, was placed on Election Day to 112,000 voters in Baltimore and Prince George’s County, the state’s two largest majority-African American jurisdictions. Recipients were told by an unidentified woman that they could “relax” because Gov. Martin O’Malley (D) had been successful.

The guilty verdict not only sullied the three-decade career of one of Maryland’s best-known political operatives, it also served as a major embarrassment for Ehrlich, the state’s only Republican governor in a generation.

Although prosecutors have never suggested that Ehrlich approved the calls, he is pushing a new book that draws anecdotes from his four years in Annapolis and contends his failed comeback bid last year was “swamped” by the black vote.

The jury convicted Schurick — who got his start in politics working for Democrats — of trying to influence votes through fraud, failing to identify the source of the call as required by law and two counts of conspiracy to commit those crimes.

Defense attorney A. Dwight Pettit, left, talks about the jury's decision after Paul Schurick, former campaign manager for Gov. Robert L. Ehrlich Jr., was found guilty of election fraud for his role in an Election Day 2010 robocall. (Kim Hairston/BALTIMORE SUN)

Schurick’s defense argued during the week-long trial that he relied on the judgment of a campaign consultant hired to reach out to black voters, who said the calls would make use of “reverse psychology” and motivate potential Ehrlich supporters to go to the polls.

The consultant, Julius Henson, is scheduled to stand trial in February, about a week before Schurick’s sentencing is set.

Schurick, 55, declined to comment outside Baltimore City Circuit Court. His lead attorney, A. Dwight Pettit, said he would appeal the case, arguing that a law used to convict Schurick amounts to an unconstitutional violation of free speech.

“This is just Round 1,” Pettit vowed to reporters.

State Prosecutor Emmet C. Davitt said he hopes Schurick’s conviction will send a message that political dirty tricks can be crimes.

“This wasn’t political speech,” said Davitt, who argued the case. “It was fraudulent.”

Davitt, who was appointed by O’Malley, also dismissed suggestions made by some Schurick sympathizers that the prosecution was politically motivated. Davitt noted that the case was initiated by his predecessor, an Ehrlich appointee.

Davitt declined to say what he would recommend as a sentence. Two of the four counts carry maximum sentences of five years. The other two carry up to a year.

Pettit indicated he would push for something far more lenient, citing a parade of witnesses — including Ehrlich, former governor Marvin Mandel (D) and former Republican National Committee chairman Michasel S. Steele — who testified to Schurick’s good character and distinguished career.

In his opening statement and closing argument, Davitt urged jurors to stay focused on the words used in the robocall, which he said was “the primary evidence” in the case. The calls began at 5:54 p.m. on Nov. 2, 2010, a little more than two hours before the polls closed, prosecutors said.

“Hello. I’m calling to let everybody know that Governor O’Malley and President Obama have been successful,” the call said. “Our goals have been met. The polls were correct, and we took it back. We’re okay. Relax. Everything’s fine. The only thing left is to watch it on TV tonight. Congratulations, and thank you.”

Both sides agreed that, whatever the legal implications of the tactic, the robocalls could not have had much impact on the outcome of the race, which O’Malley won handily — by 268,642 votes. That translated into a margin of more than 14 percentage points.

In his closing argument Monday, Pettit conceded that the tactic might have been “stupid,” but he argued to jurors that Schurick’s limited role did not amount to a crime.

Among the witnesses called by the prosecution was Rhonda Russell, an employee of Henson’s consulting firm, who recorded and coordinated distribution of the robocalls.

Prosecutors produced a timeline showing a series of phone calls and text messages among Henson, Schurick and other Ehrlich aides as the robocall was being crafted and launched.

Prosecutors also made a good deal out of a document presented by Henson to Ehrlich aides in July that outlined broader strategies for suppressing African American votes.

Although part of that strategy was dubbed “the Schurick doctrine,” Schurick and other former Ehrlich aides testified that Henson’s broader plan was soundly rejected at the July meeting.

Pettit argued to jurors Monday that Schurick should not be blamed for the absence of an “authority line” making clear the Ehrlich campaign was behind the robocall. Pettit said Schurick assumed Henson would include it because it was a routine requirement, much like putting a signature on a letter.

Russell testified that Henson told her the authority line should be left off at the request of the client.

Prosecutors also introduced evidence that Ehrlich’s internal polling just days before the election showed him winning only 7 percent of the African American vote.

In his cross-examination of Schurick on Friday, Deputy State Prosecutor Thomas M. McDonough suggested that Schurick must have known the “only way Ehrlich was going to win was if African American turnout was as low as it could be.”

Schurick forcefully disputed the assertion, saying prosecutors had a “fundamental misunderstanding about the intention of the robocall.”

Schurick was a battle-scarred player in Maryland politics long before his association with Ehrlich.

He got his start in the 1980s as an aide to one of the state’s legendary Democrats, William Donald Schaefer, serving in his mayoral administration in Baltimore and later rising to be Schaefer’s chief of staff when he was governor.

Schurick would go on to play prominent roles in Ehrlich’s 2002 and 2006 gubernatorial campaigns and served as his communications director during his four-year tenure in Annapolis.

Staff writer Aaron C. Davis contributed to this report.