Entry-level salary

[middlechanger]

Whenever the glorious day of getting an unconditional job offer arrives, will I be able to negotiate my salary to some extent?  Is the salary in the conditional offer set in stone?  I realize that government jobs are fairly set, but how unreasonable is it to negotiate it a bit (maybe a step/grade or so....?), especially after waiting 'forever' to get cleared?  Who would I negotiate this with?  Has anyone had any success doing it?

[opp]

 :-/ The answer is yes. I was not satisfied with the intial salary and requested a higher salary. A step is reasonable, maybe two; don't expect a $10,000 increase unless the government can't survive without you. I don't know what agency you are being considered with but with the CIA, I know that your recruiter may be able to work something out for you.