legislation_cosponsors: 117-sres-261, M001111

Cosponsors for tracked legislation. Distinguishes original cosponsors (signed on at introduction) from later additions. Linked to congress_members via bioguide_id.

This data as json

bill_id	bioguide_id	full_name	party	state	sponsorship_date	is_original_cosponsor
117-sres-261	M001111	Sen. Murray, Patty [D-WA]	D	WA	2021-06-08	1