(CNSNews.com) - After four straight days of showing the presidential race tied at 46 percent for President Barack Obama and 46 percent for Mitt Romney, the Gallup poll showed a little movement on Monday with Romney taking a nominal 47-percent to 46-percent lead as the Republicans prepared to begin their national convention in Tampa, Fla.
The results were for the seven-day period from Aug. 20 through Aug. 26.
Each day since May 6, Gallup has been publishing a 7-day rolling average from a survey that interviews approximately 3,050 registered voters over the course of a week. The poll has a margin of error of +/- 2 point--so Romney's 47-percent to 46-percent lead over Obama is within the margin of error.
(From April 15-May 4, Gallup had published a 5-day rolling average in the presidential race based on a polling sample of about 2,000 registered voters.)
The seven-day averages for the periods ending on Aug. 21, 22, 23, 24, and 25 each showed Romney and Obama in an exact tie at 46 percent.
Since Gallup started tracking the presidential race in April, Romney has never received more than 48 percent support and Obama has never received more than 50 percent support.
Romney's support was at its apex in the periods ending April 16, 17 and 18, when he polled at 48 percent and Obama was at 43, 44 and 43 percent.
Obama's support was at its apex in the periods ending April 23, 24 and 26, when he polled at 49 percent, 49 percent and 50 percent. After April 26, Obama's support has never again gone as high as 49 percent.
The last time Obama's support went as high as 48 percent was in the seven-day period ending on July 20.
Gallup asked respondents: "Suppose the presidential election were held today. If Barack Obama were the Democratic Party's candidate and Mitt Romney were the Republican candidate, who would you vote for Barack Obama, the Democrat or Mitt Romney the Republican?"
Gallup says it also asks those who say they are undecided whether "they lean more toward Obama or Romney and their leanings are incorporated into the results."