legislation_cosponsors: 114-sres-565, U000039

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
114-sres-565	U000039	Sen. Udall, Tom [D-NM]	D	NM	2016-09-15	1