The chairman of the state's Democratic party is facing questions about charges he made during a trip to Las Vegas.  Randy Voller went to a casino there in March to watch basketball with his college buddies, racking up over $3,000 worth of charges on a card embossed with his name and that of the state Democratic party.  Voller says he didn't know the card was backed by the personal credit of the party's then-interim executive director - whom he had just decided to replace - and that he later decided to use personal funds to pay off the card.  But he also plans to list a portion of the costs for the trip as a political donation, because he asked his friends to give money to the party.