Chapter 1. Wave riding or owning the issue: How do candidates determine campaign agendas? The first chapter addresses the question of how the agendas for political campaigns are being determined. To do so, I develop a theoretical model with two candidates who compete for the votes of four groups of voters by choosing how to allocate their time across two different issues. The amount of time spent by a candidate discussing an issue will affect the level of uncertainty regarding a candidate's policy. I find that voter distribution determines which candidate will have an advantage in the election, and issue importance affects the time that a candidate with the advantage has to devote to the most important issue in order to win the election. In most cases, candidates are willing to discuss both issues to a certain degree, and dialogue between candidates is possible. Only when candidates disagree on both issues, which are equally important to the voters, each candidate discusses the issue upon which he agrees with the decisive group of voters.

Chapter 2. Effect of polarization on campaign agendas. The second chapter investigates how the strategies of candidates change depending on the differences in candidates' ideal policies. Two candidates with established platforms choose campaign agendas in a two dimensional policy space, where a single voter decides the outcome of the election. The voter learns about candidates' policies from their speeches. The voter agrees with each candidate on one issue only, and his ideal policies are more extreme than the candidates'. When the issues are equally important, each candidate discusses either the issue upon which he agrees with the voter, disagrees with the voters, or both issues. When one of the issues is more important than another one, one of the candidates gains the advantage and in equilibrium has a set of strategies that make him the winner of the election. The issue importance affects the outcome of the election, but has limited influence on the candidates' optimal strategies.

Chapter 3. Determinants of issue importance. The third chapter provides an explanation for the increased popularity of some issues that traditionally have not been greatly discussed in previous elections. It investigates the question of whether or not the issues become more important when two competing candidates diverge in their positions from the voters' ideal policies. I look at the 2004 presidential election and using the American National Election Survey analyze the difference in the importance of several issues based on the differences in respondents' and candidates' positions. Results indicate that issue importance increases when the voter considers one of the candidates more distant on that issue. I also find that the difference between voters' and candidates' ideal policies better predict issue importance compared to the candidates' polarization.