FORTUNE — Dear Annie: I read your column on how to ask for a raise, but I wonder, what can you do if you get a job offer from a company where you really want to work, but the salary they have in mind is less than you think it should be? I’m an experienced manager in a highly specialized area of marketing, and when I researched what comparable positions pay at various companies in the same city, I discovered that the offer my (potentially) new employer has made is at the rock-bottom of the range.
The job is a terrific opportunity, but I believe I’m worth more than what they’re offering, which is barely more than what I’m already making. How do I say this without seeming greedy, and without blowing my chances? — Hesitating to Haggle
Dear H.H.: I’m assuming you researched what those other jobs pay by looking at sites like Salary.com, PayScale.com, and JobNob.com, right? There’s nothing wrong with that — except that “the websites don’t tell you what benefits come with the position,” notes Christine Mackey-Ross. As managing partner of the St. Louis office of executive recruiters Witt/Kieffer, she’s a veteran of hundreds of starting pay discussions. “It’s not just about salary. For executives and seasoned managers, benefits usually make up 30% to 40% of total compensation.
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“The benefits piece of the package can be complicated,” she adds, “if you look at various kinds of insurance, including life and disability, plus bonuses and stock options, all the way down to things like car allowances and health club memberships. Very few candidates really take into account the value of all those things.” With that in mind, she suggests taking a second look at the whole offer, rather than just salary. It might be worth more than you think.
But let’s suppose you’ve already done that, and the pay they’re offering still looks too low. “You certainly can ask why,” says Mackey-Ross. “Just be careful. Going in with the data you’ve collected and saying, ‘According to this, my market value is X’ sets the wrong tone. It’s too adversarial, especially if you’re negotiating with someone you’ll be reporting to in the new job.”
Instead, she suggests, “Say something like, ‘From the market research I’ve done, the figure I was expecting was closer to X. Would you mind walking me through how you arrived at Y?’ You want this to be a real negotiation, not a confrontation.” Four other tips for boosting the odds that you’ll get the pay you want:
1. Know your priorities. Mackey-Ross asks candidates to make a three-column list: What they feel they must have in order to take the offer; what is optional; and what they care least about and would be willing to give up in order to get something else. “The items on this list, and which category they fall into, can vary quite a lot from one person to another,” she notes. “But you need to go into the negotiation knowing exactly what you really want, or need, and at what point you’re willing to walk away.”
2. Consider requesting a later increase. If the salary figure the company has in mind is set in stone, ask whether they’d be willing to commit to a raise or a performance bonus in six months or a year, when you’ve had a chance to prove yourself in the new job. This is most likely to work if you also stress how much you want the job. “Saying how excited you are about this opportunity might seem to give you less leverage, not more,” Mackey-Ross notes. “But it doesn’t, because employers really want motivated employees.”
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3. Rehearse beforehand. “Lots of people have little or no negotiating experience, so the whole idea makes them nervous,” Mackey-Ross says. If that applies to you (and the way you signed your question suggests it does), get all your facts and priorities together and find a friend to practice with: “Have them shoot responses at you, like, ‘Sorry, this is what we pay people at your level, take it or leave it,’ and practice what you would say in the real discussion. The more you prepare ahead of time, the calmer you’ll be when you get there.”
4. Take the long view. “Think about how this job will affect your whole career,” Mackey-Ross advises. “There are often intangibles — like how great this company and this position will look on your resume, and how it could qualify you for a bigger job later — that might be worth an ‘opportunity cost’ of a lower salary than you’d like in the short term.”
Starting pay is just that, she adds: “Once you’ve proven what you can do for the company, your salary will almost certainly go up. You’ll get other opportunities to negotiate for more money as time goes on. This isn’t your last chance.”
Talkback: Have you negotiated higher pay than the initial offer when starting a new job? What worked for you? Leave a comment below.