HARRISBURG - Election Day may be 17 months away, but the race for attorney general is on.

With an embattled incumbent in office, the 2016 field of candidates could become crowded, political observers say. At least two Republicans and one Democrat are eyeing a run for the office now held by Kathleen G. Kane.

"There's a strong perception that this is a seat that is fairly open, given the attorney general's struggles over the last few years," said Christopher Borick, a political science professor at Muhlenberg College. "Therefore, you see very strong interest on the parts of Republicans and, quite likely, Democrats."

On Wednesday, Sen. John Rafferty (R., Montgomery) became the first to officially enter the race, citing a "black cloud" over Kane's office.

"I want to bring integrity back to that office," Rafferty said, referring to the controversies surrounding Kane.

Kane, a Democrat serving her first term, has pledged to run for reelection. But she is facing potential criminal charges over the leaking of secret grand jury information to embarrass a political rival.

Other Republicans considering running for the seat include Rep. Todd Stephens, who spent 10 years in the Montgomery County District Attorney's Office. Stephens said he was thinking about running because he is an experienced prosecutor. "I think there's interest in putting forth a candidate who has significant law enforcement experience," he said.

Stephens said he did not know when he would decide if he would run, and declined to comment Wednesday on Kane's work in office.

"There'll be plenty of time to discuss that down the road if it becomes relevant," he said.

Kane could also face a challenge within her own party.

Among the Democrats said to be considering a run are Josh Shapiro, chairman of the Montgomery County commissioners and a former state representative. Reached Wednesday, Shapiro declined to comment.

Rafferty's announcement came early, Borick said, and early interest is likely connected to the perception that Kane is vulnerable.

Rafferty also launched a campaign for attorney general in 2012, but dropped out after Gov. Tom Corbett supported Cumberland County District Attorney David Freed, who lost to Kane.

Rafferty announced his campaign and endorsements from state troopers and firefighters Wednesday, saying his career has been devoted to law and order.

As a state senator, he said, he has supported laws involving penalties for DUI and gang violence, and protections for children from sexual predators. If elected, Rafferty said, he would focus on integrity and would work to "right the ship of the Office of Attorney General."

Though he was critical of the current state of the Attorney General's Office, Rafferty did not mention Kane by name in his brief speech at the Pennsylvania State Troopers Association headquarters.

He said the controversy surrounding Kane did not prompt him to run. "I've always wanted to be in criminal prosecution," he said.