Political delegates from Virginia's AFL-CIO labor unions today overwhelmingly endorsed Henry E. Howell for the Democratic nomination for governor, rejecting their leaders' recommendation that they remain neutral.

Howell told reporters immediately after the endorsement by the union's Committee on Political Education COPE) that he now hopes the "rank and file of union membership will contribute an average of $5 each" to his campaign. With 80,000 union members in the state this could give Howell the $400,000 he says he needs to finance the rest of his primary campaign against former Attorney General Andrew P. Miller.

Although there is some disagreement among experienced campaign workers over how much money and how many workers the union endorsement will actually yield, there is no disagreement that the endorsement was cricial for Howell. Union support has been an essential element in Howell's two previous races for governor, and a refusal to endorse him this time could have been interpreted as a withdrawal of support.

Miller supporters tried to persuade the unions not to endorse a primary candidate and an 11-member scrreening committee of the state AFL-CIO leadership recommended neutrality in the race. Sources on the screening committee said its secret vote was 7 to 4.

Without debate, the convention also endorsed by acclamation two Arlington Democrats seeking the other two statwide offices - Dels. Ira M. Lechner, who is running for lieutenant governor, and John L. Melnick, who is running for attorney general.

The union endorsement was also seen as essential to Lechner's campaign because he is opposed by two well financed candidates - Del Richards S. (Major) Reynolds of Richmond and Charles S. (Chuck) Robb of McLean. Lechner is hoping for union campaign workers to counter their spending.

Both Howell and Lechner represent labor union's in their law practices, but Melnick has never been as closely identified with organized labor as Lechner.

Melnick's union endorsement, which came with an ease that surprised some, will increase his statewide recognition in a major way. The other attorney general candidates in the Democratic primary are Del. Edward E. Lane, a Richmond conservative, and John L. Schell, a McLean lawyer compaigning on his record as a consumer advocate.

Immediately after his endorsement Howell told reporters he considered union backing "very critical to victory."

But after 30 minutes of often emotional speeches by local union delegates praising Howell's long support of organized labor and attacking Miller positions as anti-union, the conventional delivered a decisive victory to the former lieutenant governor.

A motion to endorse Howell was approved by 74 per cent of the delegates, 486 to 170. National COPE rules require a two-thirds majority for political candidate endorsements.

Immediately after the endorsement vote, Howell told a press conference that he considered the union backing "very critical to victory." He said he now hopes that "the rank and file of union membership will contribute an average of $5 each" to his campaign.

With 80,000 AFL-CIO members in the state to draw upon, a $5 average would give Howell the additional $400,000 he said he hopes to receive in his primary campaign. He said he already has spent "about $200,000." Miller has set a primary campaign budget of $1 million.

Union contributions to Howell exceeded $300,000 in 1973 when he ran as an Independent and was barely beaten by Republican Mills E. Godwin. The heavy union spending in a losing cause in 1973 and the obvious desire of the leadership to go with a winner this year are given as the reasons for their reluctance to back Howell against Miller.

Nevertheless, state AFL-CIO president Julian Carper told the convention he was "not at all unhappy with this decision" and offered a resolution calling on unions to contribute $2 for each dues-paying member to the campaign effort.

It passed easily. Both unions and corporations are permitted to make political gifts in Virginia.

In the colorful debate on the endorsement, iron worker John P. Stublen of Norfolk said, "I'm ashamed to be identified with labor, but Henry Howell is not. He has always been with us and he wants our help now."

Longshoreman Donald R. King of Norfolk expressed his dismay over the leadership recommendation this way: "It puts me in an awkward spot. On the docks you can always find a place to throw up when you are sick of something, but I don't know what you can do in an auditorium like this."

Martin Vest, an International Ladies Garment Workers Union official from Roanoke, along with many other speakers attacked Miller's support of Virginia's right to work laws and his opposition to collective bargaining by public employees.

Walter Bierwagen, of the Amalgamated Transit Union that represents Metro workers in Northern Virginia, said, "Henry is fighting for our support but no one in his right mind can believe Andy Miller can get the support of rank and file union members."

Support for Miller in the form of votes for no endorsement was concentrated among Seafarer International Union members in Norfolk, members of the Tobacco Workers union and others in the Richmond area and in a variety of unions in Northern Virginia.

John Quackenbush, secretary of the Building Trades Council of Northern Virginia, summed up the attitude of the opposition.

"I've gone to the well for Henry Howell before, but now the well is dry, Henry Howell is not the same man for labor that he was five years ago or 10 years ago."

He added, "If the election were held today in Northern Virginia there would be an overwhelming victory for Andy Miller. This is no time to choose among our friends. We should remain neutral."