The first position on Googles search result page achieves usually most clicks. However this is also the most expensive position. Give it a try if the second to fourth display position gives you more visitors and more customers for less money.
The position of the Adwords-ad is determined not only by the maximum click price that you are ready to spend. Google evaluates also the relevancy of the displayed ad in order to position the Adwords-ads. The more clicks your ad receives, the higher it gets listed.
The headline in the Adwords-ad must catch the viewers attention. If you implement the keyword in the header line, you receive considerably more clicks onto your ad.
In the ad-text mention one or two reasons, why the internet user should click on it.