State Senators return to Dover for a special session called by Governor Jack Markell.   Work in the Senate gets underway around 4 p.m. as lawmakers consider several nominees for judicial vacancies.  Markell has nominated current Court of Common Pleas Judge Eric Davis and Chief Deputy Attorney General Charles Butler to fill a pair of vacancies on Superior Court.  The Senate will also consider a few other nominees, including Vice Chancellor John Noble's reappointment for another twelve-year term as Vice Chancellor of the Court of Chancery.