As he campaigned in the most closely watched congressional race in Maryland, state Sen. Rob Garagiola had an advantage his fellow Democratic candidates envied: the support of the politically powerful labor movement.

More than a stamp of approval, endorsements from unions that represent teachers, health care workers and government employees also brought an army of volunteers to a campaign with the aim of getting voters to the polls.

But despite labor's support, the Germantown attorney lost to John Delaney in Maryland's 6th Congressional District by 25 percentage points in Tuesday's primary election.

The rout, observers said, raises questions about the power of unions, just as Democrats gear up to take on Republican Rep. Roscoe G. Bartlett in a general election race that will help decide control of the House of Representatives.

"Labor in Maryland is not what it used to be," said Matthew Crenson, a political science professor emeritus at the Johns Hopkins University. "It's not blue-collar labor. It's public employee labor. And they tend to be more independent politically."

Garagiola's loss comes two years after most of the same groups backed Joseph Bartenfelder for the Democratic nomination for Baltimore County executive. Kevin Kamenetz, who had less labor support, beat Bartenfelder by 8 percentage points for the nomination and went on to win the general election.

Those political losses coincide with an overall decline in the number of people represented by unions in Maryland — from 392,000 in 2001 to 348,000 last year, according to the Bureau of Labor Statistics. That's a 2.5-percentage-point drop in the share of workers that organized labor can reach.

Maryland's labor leaders warned against drawing conclusions from the 6th District. They said the Maryland and District of Columbia AFL-CIO likely prevented a messy primary in the 4th District this year when it offered an early endorsement to Rep. Donna F. Edwards over former Prince George's County prosecutor Glenn Ivey.

Ivey, who has flirted with a run for the seat in each of the last two cycles, dropped out of the race before formally entering.

Labor leaders also point to the strong labor showing for Gov. Martin O'Malley's re-election bid in 2010, a year when Democrats elsewhere ran into trouble, even in traditionally blue states. O'Malley beat Republican former Gov. Robert L. Ehrlich Jr. by 14 percentage points.

But labor officials say they are less organized in the battleground areas of the 6th District, namely portions of Montgomery and Frederick counties, than they are in Baltimore and Prince George's County.

It is also difficult to energize volunteers for a primary when the candidates mostly agree on the issues, they said.

Garagiola was also never able to match Delaney's financial resources, which paid for television and radio advertising, phone calls and a stream of direct mail.

"The bottom line on this is that this guy pulled a Mitt Romney. He just spent, spent, spent," Patrick Moran, director of AFSCME Maryland, said of Delaney. "That's very difficult to compete with."

Fred D. Mason Jr., president of the state AFL-CIO, said some of his members reported seeing three or four pieces of mail from Delaney before they got their first from Garagiola.

"Not to be doing Monday-morning quarterbacking, but we found through phone calls and door knocking that there were many people … that had not received literature from the candidate," Mason said. "I'm satisfied that we did our job."

As expensive as the race for the Democratic nomination was, the general election will be even more costly. In the primary, candidates in both parties spent $2.7 million through mid-March, making it the 10th-most-expensive race in the country, the Center for Responsive Politics found.

Delaney and Garagiola both worked to court union members. Garagiola frequently mentioned his endorsements. Delaney rarely failed to note he studied at Columbia University on a scholarship from his father's electrical workers union.

Delaney, a Potomac banker, was tripped up by a report from a nonprofit group he created last year to study ways to diversify the state's economy. One section noted that Maryland law promoted collective bargaining more than neighboring states.

In response to criticism on the issue, the Democrat repeatedly said he supported Maryland's union laws. Aides noted the report was not Delaney's opinion but rather the finding of the group of business leaders.

But the damage was done. Some unions attacked Delaney over the report, calling him "dangerous" for middle-class families. Others, such as the SEIU and the AFL-CIO, refrained from criticizing him and instead focused on Garagiola's pro-labor record in the General Assembly.

Union officials, including Mason, said they are likely to move quickly toward endorsing a candidate in the general election. And while they can't say how their members will vote, if history is any guide, the groups will back the Democrat.

Terry Cavanagh, executive director of SEIU Maryland, said Delaney's money was a factor but added that he also ran a solid campaign.

Delaney "avoided rookie mistakes," Cavanagh said. "His momentum was so important."

Sean Johnson, director of legislative and political affairs for the Maryland State Education Association, said his members would begin the process of picking a candidate in coming weeks.

"In the general election," he said, "our ability to sway support will be even greater."

john.fritze@baltsun.com

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