Maybe this helps explain his Republican/ Libertarian views (sorry if this is rehashed stuff, it's new to me). Apparently he's a member of the Republican Liberty Caucus. Here's their principals and purpose, which gives reason to Paul's ties :
Principles
The following is the published list of the RLC guiding principles
The Republican Liberty Caucus supports individual rights, limited government and free enterprise.
We believe every human being is endowed by nature with inherent rights to life, liberty and property that are properly secured by law. We support a strict construction of the Bill of Rights as a defense against tyranny; the expansion of those rights to all voluntary consensual conduct under the Ninth and Tenth Amendments; and the requirements of equal protection and due process under the Fourteenth Amendment.
We support the Constitutional restrictions on federal government powers enumerated in Article I, Section 8 as an absolute limit on all government functions and programs. We oppose the adoption of broad and vague powers under the guise of general welfare or interstate commerce.
We oppose all restrictions on the voluntary and honest exchange of value in a free market. We favor minimal, equitable, and fair taxation for the essential functions of government. We oppose all legislation that concedes Congressional power to any regulatory agency, executive department, or international body.
We support the Constitution as the supreme law of the land, the republican form of government it requires, and the right of all citizens to fair and equitable representation.
We believe these are also the proper positions of the Republican Party.
Purpose
The following is the purpose or goal of the RLC in every state.
After decades of New Deal and Great Society social activism ... combined with the rapid decline in civics and American history education in the United States government-run public schools ... mixed with a growing population of ill-informed and apathetic voters ... government at every level in this country continues to be too big, too intrusive and too expensive.
Founded in 1990, the Republican Liberty Caucus works to advance the principles of limited government, individual liberty and free markets within the Republican Party and throughout the United States. Republican Liberty Caucus candidates focus on a broad range of issues, including education, taxation, property rights, gun rights, free speech, federalism and the proper role of government.
In addition to giving disenfranchised smaller-government Republicans a home by creating incentive to stay in the Republican party, the Republican Liberty Caucus helps avoid a potential exodus to Libertarian, Constitutional, and other third parties, which would open the door to big-government victories from leftist candidates. The Republican Liberty Caucus is proud to promote the GOP's smaller-government message. Limited government, individual liberty and free market ideas will win by inclusion.
While rolling back decades of government "nannyism" will require a great deal of public education and grassroots lobbying, the most important means of changing public policy is to change public officials. Therefore, the Republican Liberty Caucus works to elect pro-liberty Republicans to offices at all levels, partisan and non-partisan, in both primary and general elections.
The Republican Liberty Caucus is committed not to just electing more Republicans ... but better ones, as well.