I'm about to start a contract-to-hire position at a new company. During the four-month contract period, I will technically be an employee of the recruiting agency who found me for the position at an hourly rate. Once the contract period is over, I will become a direct salaried employee of the company. My salary will most likely be $6000 less than what I'll be earning during the contract period, however I will receive additional benefits like discounted health care, life insurance, sick leave, etc. The recruiter did go to them with a salary range of +/- 5K but I'm pretty sure that unless I speak up, I will most likely receive the lower end of the range.
Is it acceptable for me to try to renegotiate my salary at the end of the contract period? Or would this be considered unprofessional? I'm hoping that the company may be willing to pay more once they see the caliber of work I do but I don't want to risk getting fired by coming across as double-crossing or dishonest.
I have no intention of leaving the company after the contract period because I don't want to have any short-term employment on my record but I'm considering looking for other offers that could be used as leverage.