A couple of key votes are expected today at President Clinton’s impeachment trial, with hopes dwindling for a quick end to the proceedings this week. Republicans are expected to defeat Democrat Robert Byrd’s motion to dismiss the case. A largely party-line vote is also expected on a motion to depose witnesses. Senators met privately last night amid a renewed push for a bipartisan trial timetable. If such a deal is worked out, the trial could end by mid-February, perhaps sooner.