Freshman Rep. Bill Keating (D-Mass.) is a political survivor.

He squeaked out a victory in the 2010 primary for his seat, winning against ex-state Sen. Robert O’Leary by only 1,297 votes. And he won his seat in Congress with 47 percent of the vote after a brutal battle with a Republican and a few independent candidates. In redistricting, his 10th district was eliminated and replaced with a new 9th district that didn’t include his home in Quincy.

But Keating managed to land on his feet, changing his primary residence to a summer house on Cape Cod and entering the race with all the benefits of incumbency.

On Wednesday, Keating caught a break. O’Leary won’t run against him in the primary, giving Keating a clearer shot to another term. There are no serious GOP contenders for the district currently in the race, which Roll Call rates as Safe Democratic.

But local District Attorney Sam Sutter is running for the seat. Although he is considered unlikely to knock off Keating, who has endorsements from the SEIU, the AFL-CIO, Massachusetts Democratic Reps. Barney Frank and Jim McGovern, and Sen. John Kerry (D-Mass.), Sutter told Roll Call he’s running a full-fledged campaign.

The DA’s main beef with Keating: He hadn’t changed the way a broken Congress works. “I haven’t seen that he did anything to change the equation in Congress this past year. Congress is at a standstill,” Sutter said. “And, as I say to people, ‘If you can’t promote yourself in this business, you shouldn’t be in this business.’ I was a more effective DA in Bristol County than he was in Norfolk County, and I encountered larger problems than he did.

“I think I can be a more effective Congressman for the same reasons,” he added.

But Democrats in the Bay State have their doubts.

“Sutter’s not a nonentity. He does have some constituents, he’s an elected official,” an unaligned Massachusetts Democratic strategist said. “But he’ll hit up against the wall pretty soon.

“Sutter’s campaign is a classic example of someone running to increase their name ID and viability for something else” down the line, the strategist explained.

Other Democrats noted that fundraising would be his biggest hurdle.

“I don’t see Sam Sutter raising money,” said unaligned Bay State Democratic consultant Scott Ferson.

Sutter replied that “money shouldn’t decide this race.”

“They would have a different view if they had seen the poll I have,” Sutter added, although he refused to share the poll with Roll Call or provide details about it.

Keating said he was ready for whatever primary came his way.

“I take nothing for granted, never have,” he said. “I’ve seen a lot of people make that mistake.”