Likely Versus Registered Voters
One of the aspects that makes Rasmussen polling unique from many other pollsters is the use of self-identified likely voters, instead of self-identified registered voters. This is may make results more accurate, since many registered voters do not necessarily participate in every election. On the other hand, a respondent stating willingness to vote in an election may not always turn out when election day comes around. Polling experts are generally divided as to whether asking a respondent whether he or she is registered, or likely, to vote consistently results in more accurate polls.
Romney vs. Obama: Interpreting the Poll Results
Rasmussen is sometimes criticized by polling experts for sampling methods that include such traditionally discouraged practices as internet polling, automated interviewing, and weighting for political affiliation. However, aggregate polling data does suggest Romney may be gaining some momentum in the past week, as another poll released by Fox News had Romney leading Obama by 2 points over the same period of time the Rasmussen poll was conducted. Polls conducted the previous week had Obama leading by 7 to 8 points.
Rasmussen. Daily Presidential Tracking Poll. Accessed April 13, 2012.
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