The Teamsters got a big boost from Congress when the house slipped language into the bill that gave unions a big boost in organizing UPS rival Fedex. As the Wall Stret Journal reports:
If you can't beat 'em, have Congress hobble 'em. That's the motto of some in corporate America, and Exhibit A might be United Parcel Service's campaign to get Washington to impose its labor woes on rival Federal Express. This would be one more union bailout at the expense of business competition and economic efficiency.
House Transportation Chairman James Oberstar (D., Big Labor) last year slipped 230 words into a spending bill that would make it easier for the Teamsters to unionize FedEx. This ambush was included at the urging of UPS, which has been saddled with the Teamsters for decades and wants FedEx to feel its pain.
Since FedEx began its Express letter and package service in 1971, its overnight delivery has been regulated under the Railway Labor Act. Congress created that statute to discourage labor strikes and "avoid any interruption to commerce." It viewed airlines and express-shipping companies as bedrocks of commerce and deliberately put them under the law. As FedEx delivers 85% of its parcels by air, many of them time-sensitive packages that enable a modern economy, it rightly belongs under the railway act.
Reason.tv has an excellent video on the the politics behind the effort.