A shortage of qualified candidates is an indicator that your stated salary range doesn't line up with the market rate for your job description.
I applied for a position at a company a year ago and was a great fit (both from my perspective and a company rep) but my salary expectation was higher than their budget. That position remained open on their website until about a week ago. What happened a week ago? They sent an email to my almamater highlighting the position and included their current salary range. Guess what - the salary I was asking for last year fell smack in the middle of that range and they were inundated with applications!
edit: silly typos!