You may ask any full time Government faculty member to be your advisor (not those listed as Visiting, Adjunct or Emeritus, please). If your freshman advisor was in this Department, you may ask him or her to serve as your major advisor, but you may also ask someone else. It is possible that the professor you first ask may be on leave of absence or otherwise unable to help that semester; if you do not have another person in mind, feel free to ask the Department Administrative Coordinator for a recommendation.
If you need to or would like to change advisors after you have declared your major, you may do so by getting approval from your new advisor; you must fill out a Change of Advisor form [pdf] and get his/her signature. You do not need approval from your previous advisor to make such a change. Note: You do not need to fill out this form in order simply to shift from your freshman advisor to your major advisor.
Meeting with your major advisor
It will save you and your advisor time if you fill in the first page of the Declaration of Major Form [pdf] before meeting. Write down (perhaps in pencil) courses that you believe will satisfy your major requirements. The Office of Academic Advising has a worksheet [pdf] that can help you with this. This schedule is not binding in any sense, but it is extremely helpful in making sure you know what you need to do to fulfill proficiency, curriculum, and major requirements. Be sure to check the catalog or the dynamic schedule to see the semester in which courses you need are likely to be offered.