NEW YORK (CNNMoney.com) – A thumbs-up this week from the United Auto Workers on a revised version of a pension reform bill helped smooth the way for its passage in the House of Representatives on Thursday afternoon.

The thinking was that UAW support would attract just enough Democrats needed to ensure the bill's passage. The final vote was 294-132.

The House bill proposes changes both to qualified retirement plans such as 401(k)s and IRAs to ensure they are more widely used, and to company pensions to ensure they are better funded and pose less of a risk to the Pension Benefit Guaranty Corporation (PBGC), which ensures that workers receive minimum pension payments if their companies terminate their pension plans.(See correction.)

The PBGC has a long-term deficit of about $23 billion, as a result of the terminations of several large plans in the airline and steel industries.

The Senate already passed its own pension reform bill, which tackles the same issues but not always in the same way as the House bill.

It is expected that negotiations between the House and Senate to determine which elements make it into the final pension legislation won't occur until lawmakers return at the end of January.

The revisions that brought the UAW on board with the House bill concerned the conditions under which pension benefits would be frozen and conditions under which a pension plan would pay shutdown-benefits, which workers receive when a plant closes down.

Under the original House bill, if a plan's assets fall below 60 percent of its liabilities it would be deemed "at risk" and benefit accruals would be frozen. But the bill also would have prevented companies from counting any credit balance toward the plan's asset value. A credit balance results when a company pays more into its pension plan than the minimum required in a given year.

The concession by House lawmakers was to amend that provision so that a company would have to count enough of its credit balance to make sure its plan doesn't go below the 60 percent funding level. The change means there would be less chance that a plan would freeze its benefits if it could be reasonably expected to make future payments.

The second revision had to do with treatment of shutdown-benefits.

The original House bill prohibited shutdown-benefit payments from a company's pension plan. But the bill was amended to allow for shutdown-benefits if a pension plan has at least 80 percent of the assets it needs to meet future liabilities.

"The bill could have forced employers with well funded pension plans to freeze pension benefits and credits and could have prevented companies from negotiating pension benefits to cushion plant closings and layoffs," the UAW said in a statement.

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Correction: In an earlier version of this article, the PBGC was incorrectly described as taxpayer-funded. In fact, the PBGC is not supported by general tax revenue, but rather by insurance premiums from employers that sponsor insured pension plans, money earned from investments and the funds received from pension plans it takes over. CNNMoney.com regrets the error. (Back to story.)