Well, as guessed, the mysterious pronunciation of “divisive” by Tom Daschle was, in fact, di-VISS-ive /dəˈvɪsɪv/ – so far of 76 people who’ve taken my poll, precisely one shares that pronunciation; and she is Swedish. It’s seven each for di-VIZZ-ive /dəˈvɪzɪv/ and di-VIZE-ive /dəˈvaɪzɪv/, with a certain Belfast/Baltic bias for the first, and a slight Scottish preference for the second, but nothing too systematic. I’m with the 80% who say di-VICE-ive /dəˈvaɪsɪv/. So perhaps we have established a distinct Stockholm/South Dakota pronunciation of the word.

For the other variant, the “trap/bath” split, basically the question being do “crass” and “class” rhyme for you, we who think they do rhyme outnumber youse who think they don’t rhyme by two to one. There’s a fairly obvious southern England grouping who pronounce the two vowels differently, joined by the odd Australian, and a few dissident Americans, Scots, and Irish (including, er, my brother). There’s an interesting Wikipedia article about this here.