Gene Katsanis calls it his "mobile billboard," a form of advertising that is sure to grab the public's attention. But may the Jefferson Parish School Board president pay for his billboard -- a bright yellow Hummer now adorned with campaign signs -- with campaign money? The answer is yes, as long as it is used exclusively for campaigning or to fulfill the responsibilities of elected office, state ethics Administrator Kathleen Allen said. The same applies for gasoline, insurance and other related expenses. "The issue is whether it is being used for the purposes of campaign or in the holding of public office," Allen said. "There has to be some justification."