The Fox News poll is based on landline and cell phone interviews with approximately 900 randomly chosen registered voters nationwide and is conducted under the joint direction of Anderson Robbins Research (D) and Shaw & Company Research (R). For the total sample, it has a margin of sampling error of plus or minus 3 percentage points. When necessary, minor weights are applied to age, race and gender variables to bring the sample into conformity with the most reliable demographic profiles. Fox News polls are not weighted by political party. Results from Fox News polls before February 2011 were conducted by Opinion Dynamics Corp.