They vote how the archbishop tells them, and who tells the archbishop? Their king in his pointy hat what sits on his throne in Rome.
Surprising news, if it's accurate: John L. Allen, the highly regarded Vatican correspondent for National Catholic Reporter, projects that employees of the Holy See are split 60-40 in favor of Kerry. That's quite a bit better than Kerry is said to be doing among Catholic voters in the USA, and Allen notes that the vote would probably change if you only counted red hats:
First, the estimate of 60-40 support for Kerry is based on the assumption that all personnel of the Holy See would vote. If the focus is just on the cardinals and other senior officials, the balance would probably shift in favor of Bush. Second, that 60-40 split in favor of Kerry represents a change from the 2000 election, when I suspect a similar straw poll in the Vatican would have found at least a 60-40 vote in favor of Bush over Al Gore. In that sense, it's not an endorsement of John Kerry, who frankly is even less known in Rome than to many Americans, so much as opposition to Bush, above all his foreign policy.
The methodology boils down to: Anybody who works in an international-affairs section is going for Kerry. But Cardinal Renato Martino, president of the Council for Justice and Peace (which Allen fingered as pro-Kerry), has objected, in true hierarchical style, that Allen "did grave damage to the understanding of [his] readers" by not being more mealymouthed. Anyway, neutrality is being preserved, much to the consternation of this person.
Meanwhile, check out this godawful instructional film for Catholic voters and you'll wish Martin Scorcese had realized his ambition to become a priest.