Gallup analyzes what went wrong with its election polls Officials of the Gallup organization on Tuesday identified four problems that contributed to causing the nation's best-known polling organization to produce embarrassingly incorrect results in last year's election. Through much of the election year, Gallup's polls showed Republican Mitt Romney doing better than did surveys by several other leading firms. Gallup's final, election-eve poll showed Romney ahead by 1 percentage point. In reality, President Obama won by nearly 4 points. Gallup's final results were further off than almost any other major firm, decidedly "not where we wanted to be," the organization's editor in chief, Frank Newport, told reporters at a briefing Tuesday. Shortly after the election, Newport announced a major research effort to try to figure out what went wrong. The results released Tuesday suggested no single grand cause, but a series of smaller problems, all of which skewed Gallup's result in a Republican direction. INTERACTIVE: 2012 election results Several of the problems Gallup identified validated complaints by Democratic campaign aides who during the campaign year had challenged Gallup's polling methods. One significant problem involved how Gallup tries to determine which potential voters are actually going to cast ballots. The firm's surveys of all registered voters showed Obama leading, but among those deemed likely to vote, it showed Romney leading. Gallup currently uses a set of seven questions to screen for "likely voters," a procedure first developed by its founder, George Gallup, decades ago. Some of those questions appear to have screened out too many Obama voters, particularly ones that asked about past voting behavior and how much thought a voter had given to the election. Reviewing their data, Gallup researchers found indications that those questions may predict actual voting behavior differently among different groups of voters - blacks and whites, for example. The likely voter screen also may not have worked as designed in battleground states, in which both campaigns were actively targeting their supporters to get them to turn out, said Michael Traugott, a political science professor at the University of Michigan who is heading the review project for Gallup. "Polling firms don't organize the geography of the samples by focusing on battleground states versus non-battleground states," Traugott said. Since turnout was higher in battleground states, that fact may have skewed national polls. Gallup plans to test alternative likely voter models during experiments it will run using polls of this fall's elections for governor in New Jersey and Virginia. DOCUMENT: Gallup's full findings Three other problems involved how Gallup actually makes the phone calls for its polls, with all three resulting in surveying too many older, white, Republican voters. The method that Gallup used to ask people their race inadvertently led to samples with a slightly higher percentage of white voters than the actual electorate. The firm's method for choosing which numbers to call skewed results slightly toward older Americans. Gallup's methods for timing its calls made it somewhat more likely to reach voters in the Central and Mountain time zones, as opposed to the Eastern and Pacific zones. Since Obama did markedly better in coastal states, among younger voters and among nonwhites, each of those problems shifted the poll results in the Republican direction. Gallup already has changed some of its survey procedures to correct errors found by the review. Further changes are likely, Newport said, as the firm tries to ensure that in the next election it is at the "accurate end of the spectrum." Twitter: @DavidLauter