a. Multiple Studies confirm that a presidents’ influence can switch votes
Beckmann and Kumar 11 [Department of Political Science at the University of California; “How presidents push, when presidents win: A model of positive presidential power in US lawmaking”; 2011; Journal of Theoretical Politics 23(1) 3–20]
Fortunately for those inside the West Wing, some researchers paint a more optimistic picture regarding presidents’ potential for passing important planks of their legislative agenda. Covington et al. (1995), Barrett and Eshbaugh-Soha (2007), Edwards III and Barrett (2000), Kellerman (1984), Light (1982), Peterson (1990), and Rudalevige (2002) all observe that presidents secure greater support for their ‘priority’ items, and when they exert ‘effort’ pushing them. In addition, Covington (1987) concludes that White House officials can occasionally win greater support among legislators by working behind the scenes, while Canes-Wrone (2001, 2005) shows that presidents can induce support from a recalcitrant Congress by strategically ‘going public’ when advocating popular proposals (see also Kernell (1993)). Sullivan (1987, 1988) finds that presidents can amass winning congressional coalitions by changing members’ positions as a bill moves through the legislative process.