The state’s largest labor union backed a slate of Democratic candidates heading into the Aug. 13 primary election, shelling out thousands of dollars in contributions and providing extra bodies to do campaign grunt work.

The Hawaii Government Employees Association, which represents more than 42,000 state and county workers, endorsed the winner in most races.

But a closer look at the results shows the union had far greater success keeping incumbents in power — which constituted the vast majority of the 74 endorsements it announced in June — than in its rare attempts to remove a Democrat from office or influence who should fill an empty seat.

“Union endorsements can be a big deal but they can be overrated,” said Neal Milner, a political analyst and Civil Beat columnist. “Union members don’t just look at the list and say I’m going to vote that way. What they can add is manpower — putting people out in the streets to canvas.”

One of the only examples of HGEA endorsing an incumbent who lost in the primary was Hawaii County Councilman Dan Paleka’s race against Jen Ruggles, who won by 7 percent.

When it came to picking who should fill open seats on Oahu, Kauai and the Big Island, the results were split.

In the race to fill the District 29 House seat left open by Rep. Karl Rhoads, who ran for the Senate instead of seeking another term, HGEA backed Valerie Dionne. She finished last in the five-way contest that Daniel Holt won.

The union had a better outcome with its endorsement of Nadine Nakamura to replace outgoing Rep. Derek Kawakami, who is running for Kauai County Council. She easily defeated Fern Rosenstiel in the District 14 House race.

HGEA fared similarly with its endorsements of candidates who were challenging Democratic incumbents.

The union’s choice of Tommy Oi fell far short of winning against longtime Rep. James Tokioka, but HGEA’s pick of Tim Richards edged out incumbent Hawaii County Councilwoman Margaret Wille.

The union backed David Tarnas, a former two-term House lawmaker, in his attempt to unseat Rep. Cindy Evans, who was first elected in 2002. He came within 2 percentage points of defeating her, and said he’s definitely trying again in two years.

Tarnas said he appreciated the $1,000 donation HGEA made to his campaign and the limited ground support he received from a union worker assigned to his race and a couple other races.

But he said his race was less of a priority for the union, which was far busier on the Big Island helping Harry Kim become mayor and trying to install Moana Kelii, an HGEA union agent, in the Council. Kim won outright in the primary; Kelii finished second to Sue Lee Loy in a three-way race, forcing a runoff in the Nov. 8 general election.

Tarnas said he’s not sure his endorsement from HGEA helped much. Its $1,000 donation didn’t constitute much of his overall fundraising total, which was $44,360 during the election period.

“But for me it’s an important way for my candidacy to get vetted,” he said. “People still look at it as a way to evaluate a candidate. They do carry credibility.”

Evans did not return a message seeking comment Monday.

Tarnas said there seems to be an assumption that the privatization of hospitals was a fundamental campaign issue, since his opponent supported a bill last year that let Kaiser Permanente take control of three state-run hospitals in Maui County and there has been talk of doing something similar on the Big Island.

HGEA had threatened to sue the state if a deal wasn’t reached this summer to provide special severance payments or retirement benefits for hospital workers who were losing their government jobs — although the vast majority are expected to be hired back by Kaiser at comparable levels of pay and benefits.

In his discussions with constituents while campaigning, Tarnas said the hospital privatization issue rarely came up.

But it may have been why the union did not endorse Evans.

HGEA Executive Director Randy Perreira was unavailable to answer questions. The union’s spokeswoman said he was in meetings last week and off-island Monday.

The union has explained in news release that it chooses who to endorse through a member-driven process that starts with political action committees, which are made up of members. The committees’ recommendations are then reviewed by the HGEA board of directors, which is comprised of members elected by their respective bargaining units and/or island memberships.

“The unions probably have a more challenging job than they had in the past.” — David Tarnas

The candidates have to seek the endorsement from HGEA, and in some cases the union will not make an endorsement. HGEA didn’t endorse House candidates representing several Oahu districts, instead encouraging members to vote for whomever they want.

The union takes its endorsements seriously, and is even holding a meeting Tuesday titled “Why is our HGEA endorsement so important?”

But on the whole, Tarnas, who was a House lawmaker for four years in the 1990s, said HGEA and other major unions in the state are having to adapt to changing demographics.

“The unions probably have a more challenging job than they had in the past,” Tarnas said. “People are more removed from government employment than they were in the past.”

Milner said the unions may have more influence these days in passing legislation — like the special benefits for Maui hospital workers — than in getting candidates elected.