To answer your question, some of the DHL ground workers in major cities in the US are former Airborne Express workers, and most of them are Teamsters. ABX pilots are also Teamsters. So I don't think you'll see the Teamsters take a stand on the UPS side.... there's enough Teamsters on the former Airborne Express side (mainly ABX pilots) to prevent that.
I just took a look at the Teamster website and it appears the ratio is 16 UPS Teamsters for every DHL Teamster. I am inclined to believe that Hoffa is not going to create too much noise in this case, but I may be wrong. After all UPS is his bread and butter. I would think the #1 item on his agenda is to unionize the FedEx workers.
Teamsters in the DHL System = 12,500+
There’s strength in numbers and by building your union with the Teamsters, you’ll join more than more than 12,500 workers at DHL Express, ABX Air and throughout the DHL system—and some 250,000 workers in the package-sort-delivery industry—who are proud Teamsters.
Teamsters in the DHL System
Teamsters in the UPS System = 200,000+
The Teamsters Package Division serves more than 200,000 members throughout the United States. United Parcel Service is the single largest employer in the Teamsters Union, and the Division is responsible for ensuring that management abides by the National Master Agreement.
Teamsters Parcel and Small Package Division