(Bloomberg) — For 15 years, United Parcel Service Inc. has spent more money on U.S. elections than any other company. Now UPS, which has gotten its way on everything from federal highway programs to expanded routes to China, is seeking a new return on its investment.

The world’s largest package-delivery service wants Congress to allow employers to cut pension benefits already promised to some workers in plans funded by multiple companies. Atlanta-based UPS says the plans can no longer afford to pay full benefits because so many companies that used to pay into the pool have gone out of business. As the number of contributors shrinks, remaining companies are obligated to fund the retirement plans.

Lobbying Power

UPS, whose workforce of 407,000 makes it the U.S.’s fourth- largest corporate employer, spent $1.3 million during the first half of 2005 successfully lobbying for the Central American Free Trade Agreement and legislation that provided more highway funds