Mitt Romney staked his first lead over President Obama in Gallup’s Daily Tracking Poll since July 18th today, 47 percent to 45 percent.

Romney and Obama were tied in the Gallup poll this Saturday when Romney named Paul Ryan to be his running mate. Gallup’s daily tracking poll uses a seven-day rolling sample.

Obama has led by as many as seven points since Gallup began their tracking poll in April.

UPDATE: An earlier version of this post reported Gallup uses a three-day rolling sample for the Romney/Ryan number. In fact, Gallup uses a seven-day sample for the Obama/Romney number and a three-day sample for the Obama approval number.