References
- Americans for Democratic Action. 2015. “Voting Records.” http://www.adaction.org
- Bradner, E. 2015. “Poll: majority of Americans back keystone pipeline.” CNN. http://www.cnn.com/2015/01/15/politics/poll-majority-of-americans-back-keystone-pipeline/
- “Environmental Analysis of the Keystone XL Project.” 2015. Congressional Digest 94 (1): 5–7.
- Federal Elections. 2012. Election Results for the U.S. President, the U.S. Senate, and the U.S. House of Representatives. Washington (DC): Federal Election Commission.
- Gilens, M. and B. Page. 2014. “Testing Theories of American Politics: Elites, Interest Groups, and Average Citizens.” Perspectives on Politics 12 (3): 564–581. doi:10.1017/S1537592714001595.
- Hirsch, B., and D. Macpherson. 2015. “Union Membership and Coverage Database from the CPS.” http://www.unionstats.com/
- “Keystone XL Timeline.” 2015. Congressional Digest 94 (1): 2.
- Lee, D., and S. Tkachyk. 1987. “An Empirical Analysis of Congressional Voting on Farm Bill Legislation.” Cornell Agricultural Economics Staff Paper Series 87: 21.
- “Legislative Background on the Keystone XL Pipeline.” 2015. Congressional Digest 94 (1): 8.
- Leogrande, W., and A. Jeydel. 1997. “Using Presidential Election Returns To Measure Constituency Ideology: A Research Note.” American Politics Research 25 (1): 3–18. doi:10.1177/1532673X9702500101.
- O’Roark, J., and W. Wood. 2010. “Determinants of Congressional Minimum Wage Support: The Role of Economic Education.” Public Choice 147: 209–225. doi:10.1007/s11127-010-9617-6.
- Politicians & Elections. 2015. Open Secrets. http://www.opensecrets.org
- Sobel, R., and R. Lawson. 1995. “Intrastate Differences in Representative and Senator Behavior.” Journal of Public Finance and Public Choice 13 (1): 3–17.
- Wright, G. C. 1989. “Policy Voting in the U.S. Senate: Who Is Represented?” Legislative Studies Quarterly 14 (4): 465–486. doi:10.2307/439954.
- Yueng, I. 2008. “The Influence of Campaign Contributions on Legislative Voting: A Case Study of the 1996 Farm Bill.” Thesis, Department of Economics of Amherst College.