This study focuses on issues related to political advertising and electoral behavior through an examination of political advertising believability, the perceived value of information sources utilized and available in election campaigns, voter involvement, confidence, and emotion. The study was undertaken in a recent state election in Australia. Data were gathered from a sample of registered voters andanalyzed using partial least squares. The results indicate that the negative campaign run by the opposition was believed as much as the positive campaign run by the incumbent government. Also, voter involvement, satisfaction, and emotion affected the believability of the positive campaign, but only involvement and satisfaction affected the negative campaign. The findings also indicate that non-paid media (television, newspapers) were valued more as sources of information by voters than were political advertising and the Internet.