When it comes to awesome cover letter opening lines, there are a few solid approaches to consider. (youtern.com)
In addition to writing an awesome cover letter (refer to # 1), you could end off mentioning that you are willing to consider a senior role since your extensive experience will allow you to take on more responsibility (read: higher pay) (careerladder.sg)
You can see our post here on writing an awesome cover letter for more information. (zipjob.com)