Final answer:
The textbook suggests that several factors may explain why many people do not vote in the United States, including the domination of two political parties, the perception of voting as ineffective, and socioeconomic factors.
Step-by-step explanation:
According to the textbook, there are several factors that may help explain why many people in the United States decide not to vote. One reason is the perception that they lack effective choices due to the domination of only two political parties. Another reason is the feeling that their vote will not have any real impact on the outcome of an election. Additionally, socioeconomic factors such as income and education level can also affect voter turnout.