Neither she nor any other senator or congressman voted on the increase. It was done by executive order from President Bush, which I guess he can do because it's the executive branch.
Well, I suppose someone would attempt to push the technicality that the increase came about under her tenure, but if this is the case, EO, then I don't believe she should be disqualified, as she herself did not vote on an increase for a job for which she is now being considered.