“…Most research on bill sponsorship and cosponsorship focuses on lawmakers’ issue priorities rather than the policy instruments in the bills they support. Issue agendas are explained by lawmakers’ personal backgrounds and interests (Burden, 2007; Carnes, 2013; Choi, 2015; Swers, 2020; Tate, 2004), partisanship (Petrocik, 1996; Petrocik et al, 2003), interest groups (Gelman, 2017; Hall & Wayman, 1990; Rocca & Gordon, 2010), the president’s agenda if they are of the same party (Hall, 1998; Kingdon, 1989), and perceptions of constituency needs (Hall, 1998; Hayes et al, 2010; Miler, 2010; Sulkin, 2005). which can be revealed by challengers’ campaigns (Hall, 1998; Miler, 2010; Sulkin, 2005, 2011), and protests (Gause, 2020).…”