With a key straw poll looming next Saturday, the field of Republican presidential candidates continued to focus on Iowa this week, the site of the first caucus.

Former Massachusetts Gov. Mitt Romney, the current front-runner in the Republican pack, has been downplaying the straw poll, which is being held by the Iowa Republican Party in Ames, giving the rest of the field an opportunity to garner some momentum in the race.

On Wednesday, Minnesota Congresswoman Michele Bachmann, who has been surging in the polls over the last two months, released a television ad running across the Hawkeye State as she looked to solidify her credentials as the leading conservative threat to front-runner Mitt Romney. In the ad, Bachmann takes aim at President Barack Obama on the economy and repeats her opposition to raising the federal debt ceiling.