This survey was conducted by Research 2000 of Rockville, Maryland. A total of 400 likely voters were interviewed statewide by telephone between February 14 and February 16, 2010.
Those interviewed were selected by the random variation of the last four digits of telephone numbers. A cross-section of exchanges was utilized in order to ensure an accurate reflection of the state. Quotas were assigned to reflect the voter registration of distribution by county.
The margin for error, according to standards customarily used by statisticians, is no more than plus or minus 5% percentage points. This means that there is a 95 percent probability that the "true" figure would fall within that range if the entire population were sampled. The margin for error is higher for any subgroup, such as a gender or region.