BOSTON – An aide to former Massachusetts Treasurer Tim Cahill was found not guilty of corruption charges on Tuesday, but jurors did not reach a verdict on charges against Cahill and a judge asked them to keep deliberating.

Cahill and former chief of staff Scott Campbell were charged with violating state ethics laws by scheming to use $1.5 million in taxpayer-funded lottery advertisements to boost Cahill’s sinking 2010 gubernatorial campaign.

Tuesday was the sixth day of deliberations in the case.

Campbell smiled broadly after the verdict was read and Cahill gave him a bear hug and patted him on the back.

“We’re very happy,” said Campbell, who was mobbed by reporters as he left the courtroom. “We’re very relieved.”

Campbell still faces charges stemming from a separate indictment that accuses him of concealing the true identities of donors to Cahill’s gubernatorial campaign.

He also faces charges in another case in which he is accused of conspiring with the state’s former probation commissioner, John O’Brien. That indictment alleges that O’Brien organized a 2005 fundraiser for Cahill’s treasurer campaign in exchange for Campbell’s help getting O’Brien’s wife a job at the state lottery. Cahill does not face any charges in that case.

The jurors in Cahill’s case resumed deliberations Tuesday afternoon after Judge Christine Roach provided them a legal instruction given to deadlocked juries and told the panelists it would be “desirable” to reach a unanimous verdict.

She reminded them the burden to prove the case was on the state, asked them to consider each other’s opinions and said there’s no indication 12 other people could decide the case any better than they could.

“It is your duty to decide the case, if you can do so conscientiously,” she said.

The jury ended deliberations for the day late Tuesday afternoon without a verdict on Cahill and was expected to go back to work Wednesday morning.

As he left court, Cahill declined to comment on his own case but said, “I’m happy for Scott.”

Cahill, who oversaw the lottery as treasurer, is charged with conspiracy to use his official position to gain an unwarranted privilege and conspiracy to commit procurement fraud. He faces a maximum of five years in prison.

During the month-long trial, prosecutors portrayed him as a shrewd politician who approved an ad blitz touting the benefits of the lottery to run during the month before the election because he hoped it would boost his independent campaign for governor, which by that point was faltering badly. Cahill was also running separate campaign ads touting his leadership of the lottery.

But Cahill’s lawyer, Jeff Denner, said his client decided to run the ads because the lottery had been damaged by a series of attack ads the Republican Governors Association ran against Cahill.

“It was an appropriate advertising response to what was going on,” Denner said.