The main purpose of this legislation, known as the "End Dark Money Act," is to promote transparency regarding the political activities of certain nonprofit organizations. It aims to remove restrictions that currently limit the Internal Revenue Service (IRS) from using its funds to investigate and disclose the political spending of these organizations. Key provisions of the Act include the repeal of a specific restriction from a previous law that prevented the IRS from using its resources to bring clarity to the political activities of nonprofits.