We analyze a psychologically based model of voter turnout. Potential voters experience regret if they fail to vote, which is the motivation for participation in voting. Regret from abstention is inversely related to the margin of victory. Voters on the winner's side experience less regret than those on the loser's side. We show that the unique equilibrium involves positive voter turnout. We show that the losing side has higher turnout. In addition, voter turnout is positively related to importance of the election and the competitiveness of the election. We also consider scenarios in which voters are uncertain about the composition of the electorate's political preferences and show similar phenomena emerge.