The poll's focus is on Obama and then Democrats and Republicans in Congress.
poll - a factor with levels approve disapprove
eval - a factor with levels Democrats Obama Republicans
See the Pew Research website: www.people-press.org/2012/03/14/romney-leads-gop-contest-trails-in- matchup-with-obama. The counts in Table 6.19 are approximate.
Use the following R code to directly access this dataset in R.