Daily tracking results are collected via telephone surveys of 500 likely voters per night and reported on a three-day rolling average basis. The margin of sampling error—for the full sample of 1,500 Likely Voters--is +/- 3 percentage points with a 95% level of confidence. Results are also compiled on a full-week basis and crosstabs for
full-week results are available for
Premium Members.
Like all polling firms, Rasmussen Reports weights its data to reflect the population at large (
see methodology). Among other targets, Rasmussen Reports weights data by political party affiliation using a dynamic weighting process. While partisan affiliation is generally quite stable over time, there are a fair number of people who waver between allegiance to a particular party or independent status.
Since the November 2008 election, the number of Democrats in the country has declined while the number of unaffiliated voters has grown.
Our baseline targets are established based upon
separate survey interviews with a sample of adults nationwide completed during the preceding three months (a total of 45,000 interviews) and targets are updated monthly. Currently, the baseline targets for the adult population are
35.8% Democrats, 32.2% Republicans, and 32.1% unaffiliated.
Likely voter samples typically show a slightly smaller advantage for the Democrats