Gary Raub
Some clever cops helped solve a 36-year-old cold case in Maine by implementing a phony chewing gum survey” to arrest Gary Sanford Raub in the murder of Blanche Kimball. Maine State Police

Some clever cops helped solve a 36-year-old cold case in Maine by using a phony chewing gum survey” to arrest Gary Sanford Raub in the murder of Blanche Kimball.

DNA was taken from Raub, who is now homeless in Seattle, after investigators approached him with a phony chewing gum survey.

"I don't know the exact details, but we obviously needed some up-to-date DNA from him and some bubble gum was the key to getting that," Maine State Police spokesman Steve McCausland told ABCNews.com.

Raub, 63, was arrested Monday in Seattle on charges he murdered then-70-year-old Blanche Kimball in Augusta, Maine, in 1976.

Raub’s arrest 36 years after Kimball’s murder marks the oldest cold case to be cracked in the Pine Tree State.

Kimball was discovered murdered in her Augusta home from stabbing wounds on June 12, 1976 after concerned neighbors called police because they had not heard from her in days.

Raub had been a suspect in the initial days of the investigation, but authorities were unable to find enough evidence to prosecute him, the Kennebec Journal reported.

While the case went cold, authorities still kept evidence from the murder.

"In Maine, State Police assign the open homicide cases to a detective. There's always a detective assigned to these cases, which are constantly reviewed, as time permits," McCausland told ABCNews.com.

Last summer, workers with the Maine State Police Crime Lab were going through evidence that linked them to Raub, whom investigators found out had lived with Kimball at one time. The only thing missing was a DNA sample from the 63-year-old to match the samples found at the murder scene.

Raub was no stranger to Seattle police and had a “lengthy criminal record,” according to ABCNews.com, which made it easy to locate him.

"It was last summer that we got some very concrete DNA work on some of the evidence that was seized and made a comparison that brought us to this point," McCausland said. "It was DNA that cracked this."

The effort to nab Raub was due in large part to Maine State Police Det. Abbe Chabot, who was assigned to the cold case in 2003.

"The investigators of the day did a very thorough job," Maine State Major Crimes Unit Lt. Christopher Coleman told the Kennebec Jounral. "We're here today because of their efforts."

Authorities have yet to determine a motive for Kimball’s killing.

Aside from murder charges, Raub is also facing charges related to being a fugitive from justice, the website reported.

An extradition hearing for Raub is set for sometime this week. The 63-year-old faces life in prison if convicted of the charges.

Jared Mills of the Augusta Police Department said the cracking of the cold case is a testament to the department’s determination in pursuing such cases.

"The public needs to know these cases never go away," he told the Kennebec Journal. "This is a 36-year-old case that we didn't give up on. We'll never give up."