Final answer:
The option 'Negative advertising in the media has had the effect of alienating possible voters' is NOT a reason for low voter turnout for constitutional amendments. The primary factors are the amendments' insignificance, lack of controversy, and off-year election scheduling.
Step-by-step explanation:
Which of the following is NOT a reason for low voter turnout for constitutional amendments? Among the provided options, the one that is not a recognized reason for low voter turnout is that 'Negative advertising in the media has had the effect of alienating possible voters.' While negative advertising can have an impact on voters' perceptions of candidates and issues, low turnout for constitutional amendments is more commonly attributed to reasons such as the insignificance of many amendments to voters, the lack of controversy surrounding many amendments, and the fact that elections for amendments often occur in 'off' years when no candidates are on the ballot.
Other significant factors contributing to lower voter turnout discussed in provided references include the inconvenience of getting to the polling place on election day, restrictive voter registration laws, the frequency of elections leading to 'voter fatigue,' and institutional barriers such as new voting laws that may act as a deterrent to voting rather than preventing fraud.