In today's Columbus Dispatch there is a story ("Voinovich in favor of rules change") in which it says that Senator Mike DeWine "refused to disclose his position on an issue that threatens to derail most Senate business this year." This is a curious statement coming from someone who participated in filibusters of two judicial nominees which required the Senate to invoke cloture on their nominations in 2000. I hope that his silence is informed by his prior votes.
With regard to Sen. Voinovich, I do not believe that he has ever been part of a filibuster with regard to a Presidential nominee (though he was only a Senator for a few years of the Clinton Administration). Nonetheless I would point out to him that there is not one Senate rule regarding cloture on nominees and another rule regarding cloture votes on legislation. Accordingly how long will it be before the majority tires of "obstructionists" who (for example) insist on some degree of sanity in the budget process as Voinovich does. If you take away this tool with regard to nominees, then the Rule exists for any Senate action only to the extent the majority agrees the Rule should apply.