Final answer:
In the 2021 Nevada legislative session, the Democratic Party held the majority in both the Nevada Assembly and the Nevada State Senate, wielding significant legislative influence.
Step-by-step explanation:
In the 2021 Nevada legislative session, the political party that held the majority in both the Nevada Assembly and the Nevada State Senate was the Democratic Party. The Democratic majority held control which allows them to set the legislative agenda and pass laws aligned with their policy platform.
It is crucial to understand that the majority party in any legislative body has significant power to elect leadership, set agendas, and determine committee compositions, which are instrumental in shaping public policy. This reflects the broader trend where political ideologies influence the division of party control across different regions of the United States, with urban areas often leaning towards the Democratic Party.