FORTUNE — Dear Annie: A couple of years ago, I applied for a job at a company where I’ve always wanted to work. At the time, they had a hiring freeze in effect, so I got nowhere. But now I hear through the grapevine that they’ve started adding staff in the area where I would be working (brand management). So I’m thinking about trying again. My question is, since they told me they would keep my information on file, should I assume they already have my resume, etc., or start over from scratch? I’m sure lots of people apply for jobs there all the time, so I’d appreciate any suggestions on how to move to the front of the line. — Mulligan
Dear Mulligan: First, assume nothing. “If you applied two or three years ago, there is no guarantee that the same hiring managers or human resources people you contacted before are still there,” notes Roy Cohen, a New York City career coach and author of The Wall Street Professional’s Survival Guide. “Many companies have experienced so much turnover in the past few years that there is not much institutional memory anymore. So even if you got to the interview stage the last time around, you may now be having a completely new conversation.”
Cohen says that several of his clients have recently succeeded at second or even third attempts to get hired by employers who had turned them down before. “Always keep in mind that not being chosen for a particular job opening is often just a matter of numbers,” he says. “If there are three or four or six candidates and only one job, interviewers have to cull out even candidates they find really impressive.”
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Moreover, even if the right fit still isn’t there on your second try, don’t rule out a third. By staying in touch with people you meet during the application process — starting with inviting them to join your network on LinkedIn
— you can boost your chances of getting hired later, Cohen adds: “The person they do hire may not work out, or a different opening may come along, so stay on their radar screen. People would usually much rather hire someone they’re already familiar with than take a chance on an unknown quantity.”
Annie Stevens, managing partner at Boston-based executive coaching firm ClearRock, has also seen plenty of job seekers lately who have gotten hired on their second or third approach to a company. She offers these four suggestions:
1. Emphasize what’s different about you now. This is especially important if you end up meeting with the same interviewers you met last time. “In your cover letter, on your resume, and during phone and in-person interviews, highlight specific new experience and skills you’ve gained since then,” Stevens says. Be sure and include any courses you’ve taken or credentials you’ve earned.
2. Network in reverse. Use social media, and any industry contacts you have (from your previous jobs, for instance) to “seek out people who work for your target employer, or who know someone who does,” Stevens advises. “Instead of leading you to the right job, as traditional networking does, reverse networking starts with the job and leads you to people who can help you get it.” Insiders can tell you, for example, what aspects of your experience you should stress in an interview. They may even give you a referral.
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3. Join the same professional or volunteer group as the hiring manager. If you already belong to a trade association where the hiring manager is also a member, make it a point not to skip any events where you might run into him or her. “These kinds of functions provide a good, low-key way to get to know each other better,” Stevens notes.
4. Share news that adds another dimension to your qualifications. “Do something that will give you added recognition, such as writing an article for a trade publication or giving a speech at a conference, and share that information with the company,” Stevens says. “Continually remind them of the value you’ll bring to the team.”
In this as in so many other things, persistence — “but without pushing it to the point where it becomes annoying,” says Roy Cohen — often wins out. Good luck.
Talkback: Have you ever gotten a job on your second or third try? If you’re a hiring manager, what specifically would make you take a second look at a candidate? Leave a comment below.
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