(McCarty, p. 4) This gulf represents the polarization of parties that has occurred and the large gap in preferences resulting from the move of both parties to the left or right. Interestingly, such a level of partisan polarization, as exists today, has not been seen since the 1920s. (McCarty, p. 4) Second, and surprisingly, the members of each party are closely aligned on the 1st dimension of liberal-conservative measure, but on the 2nd dimension, measuring social issues, both parties, but particularly the Democrats, are polarized from within. (McCarty, p. 4) The Democrats are especially polarized across the social dimension of the DW-NOMINATE algorithm, which might explain why, even with a super-majority, they were unable to gain the support necessary for certain healthcare proposals and for invocation of cloture.
Nang kawili-wili, tulad ng isang antas ng kapanig polariseysyon, pati na umiiral sa araw na ito, ay hindi pa nakikita mula noong 1920s. (McCarty, p. 4) Pangalawa, at nakakagulat na ang mga miyembro ng bawat partido ay malapit na nakahanay sa ika-1 ng sukat ng liberal-konserbatibo pamamaraan, ngunit sa ika-2 dimensyon, pagsukat sosyal na isyu, ang parehong mga partido, ngunit lalo na ang Democrats, ay polarized mula sa loob. (McCarty, p. 4) Ang Democrats ay lalo na polarized sa buong social na sukat ng DW-magmungkahi ng kandidato algorithm, na maaring ipaliwanag kung bakit, kahit na may super-karamihan, sila nagawang makakuha ng suporta kinakailangan para sa ilang mga panukala sa healthcare at para sa pananalangin ng cloture.