Reversing a decades-long downward trend, the percentage of the American workforce in unions edged up last year, the U.S. Labor Department reported.

The change was minuscule - a tenth of 1 percentage point, from 12.0 to 12.1 - barely statistically significant. But for the labor movement, which is starved for any good news, even the tiniest upward blip is cause for encouragement.

Locally, Pennsylvania and Delaware saw gains in union membership and density.

New Jersey's membership continued to slip despite big union wins among dealers in Atlantic City's casinos and among professional and administrative staff at Rutgers University.

In Pennsylvania, "there's been a tremendous movement in health care, child care and home care," said William George, who heads the Pennsylvania AFL-CIO.

Pennsylvania's union membership grew to 830,000, 15.1 percent of the workforce, from 745,000 or 13.6 percent in 2006.

That puts Pennsylvania well ahead of the national numbers in union density.

Nationally, union membership grew from 15.4 million members in 2006 to 15.7 million last year.

Delaware's union membership also grew - to 47,000 from 43,000, and to 12.8 percent from 10.3 percent.

New Jersey continues to be among the most unionized states in the nation. In 2006, it was one of four states whose union membership topped 20 percent. In 2007, the percentage fell to 19.2 from 20.1.

In 1953, more than one in four workers belonged to a union. Since then, membership has fallen steadily, with only a few upward blips, the last in 1979. The federal Bureau of Labor Statistics adopted a new system for counting union membership in 1983.

Labor leaders say workers turn to one another for support in a tough economy, when the future appears tenuous and there is an erosion of pension and health benefits.

Right-to-work groups, which say they are not anti-union, call this upward blip the result of frantic scrambling for members by a labor movement on its last legs.

"The writing was on the wall, that if they didn't do something, they were going to go extinct," said J. Justin Wilson, a senior analyst at the Center for Union Facts, a Washington right-to-work group.

Last month, by a vote of 46-42, Cherry Hill public school custodians employed by Philadelphia's Aramark Corp. voted to join the Office of Professional Employees International Union.

An Aramark spokeswoman said the company supported workers' rights to join a union but was contesting this election.

"Every day, these workers are hurting more and more," said union organizer Seth Goldstein, whose daughters attend Cherry Hill schools.

"With this recession, if anyone needs a stimulus in their take-home pay, it's these employees.

"Unions have a real role in the economy," he said, "because the only way the middle class can push its way up and get a decent living is if they can bargain effectively."

Ironically, one of the drivers of the economic slowdown - the weak dollar - may have helped Pennsylvania union workers, the AFL-CIO's George said.

The weak dollar means that union-rich manufacturing jobs, while still in decline, are not declining as fast because some manufacturing that had been done abroad is now being done here, he said.

"Steel mills have rehired some steel workers," he said. "In addition, China is taking anything we can produce."

Casino construction across the state has boosted membership in the building trades, he said.

What the AFL-CIO's national director of organizing, Stewart Acuff, said he found most encouraging was growth in membership among younger workers, even though both the numbers and the percentages are low.

"That gives lie to the notion that young people are only interested in themselves and that the unions' day is past," he said.

Roger "Rick" Grimaldi manages the Philadelphia office of the Jackson-Lewis law firm, which regularly holds union-avoidance seminars. He said the statistical movement was so minor that it does not change the pattern. "You could argue that it's an aberration," he said.

Economist Mark Zandi from Moody's Economy.com in West Chester agrees that the change is small. "It may not be statistically different from a zero change."

But, he said, "that may be news in itself given the steady erosion in this sector."