The AFL-CIO has failed to come up with enough votes to break a threatened Senate filibuster on repel of state right-to-work laws and may drop the controversial proposal from its labor law overhaul package.

A high-level AFL-CIO legislative subcommittee discussed the problem yesterday and reportedly decided to make a final effort in the next few days to round up the 60 votes necessary to stop a filibuster, which is three or four more than the federation's lobbyists now claim to have.

If the effort is unsuccessful, sources said, the overhaul package will be introduced without repeal of Section 14(b) of the Taft-Hartley Act, under which 20 states have passed right-to-work laws banning union shop agreements that require a worker to join a union.

If 60 votes cannot be found, the repealer will be "put on a back burner," said one official, and introduced separately at a later time.

The contemplated retreat on 14(b) repeal, which was once a high-priority item on the AFL-CIO's congressional agenda, follows a series of rebuffs for organized labor on Capitol Hill. A bill to make it easier for striking unions to shut down an entire construction site was unexpected defeated in March, and the House last week attached an anti-union rider to a bill to expand political rights to federal employees.

President Carter has said he would sign a bill repealing 14(b) but not lobby for its passage, and conservatives in the Senate have been promising a filibuster against repeal. Prospects of repeal were not improved by a Gallup Poll earlier this month showing 2-to-1 opposition to union shop agreements.

The labor law package, described by union leaders as organized labor's most ambitious legislative effort in decades, contains a number of provisions aimed at making it easier for unions to organize and reach collective bargaining agreements.

But sources said it appears unlikely that it will include a key provision of a bill already introduced in the House by Rep. Frank Thompson Jr. (D-N.J.) to eliminate secret-ballot representation elections when at least 55 per cent of workers sign union recognition cards.

Instead, the source said the bill is likely to provide mandatory deadlines for representation elections to avoid protracted delays. The White House and some congressional leaders reportedly balked at the Thompson proposal, which the AFL-CIO considered including in its package, as undemocratic.