As I've previously written, the job market in almost all industries / professions / fields is in a state of heavy labor oversupply. DC may be best off compared to any other metropolitan area in this regard; in fact the November 2011 Bureau of Labor Statistics reports that there are actually more job openings in DC than there are applicants, by a margin of two to one. These statistics need to be viewed with a pretty large grain of salt, since "job openings" are calculated by looking at advertised or posted positions, and within government and many non-profits (including such behemoths as the World Bank) it is required that a job be posted for a certain length of time before it can be filled by an often previously-designated internal candidate, Nonetheless there are plenty of jobs available.
Competition for any of the more interesting ones, particularly those with good advancement, resume-building, or compensation potential, is going to be heavy. First rule of thumb: be sure that you can make at least a reasonably believable case that you meet EACH of the job requirements, and at least several of the "preferable to have" experiences. If an employer specifies that she is looking for someone with a minimum of three years working in a public relations agency and you've worked for two and a half writing a newsletter and issuing press releases for the American Washing Machine Association you could argue that you'd be able to do the P.R. job, but because you've not met a fundemental criterion you will not be considered.
you have been adept at relationship-building. There are three ways in which the strength of your relationships can trump job requirements.
First, if a senior person in an organization is willing to go to bat for you based on his previous impressions of your work, there's a good chance that you will be thrown into the pool of applicants to be considered, and at that point you can make the case as to why, for example, despite the absence of that time at a P.R. agency, you have developed relationships that will allow you to bring new business to the firm, or that you are fluent in Arabic and are willing to be posted to the Middle East, facts that can trump other considerations such as "does he have experience working in the chemical industry?" or "does he have a doctorate in macroeconomics?" After all, any job description and its accompanying specs are based either on the previously held position or, if a new position, the best guess as to what talents and skills will be essential. But there can always be wild cards that can help you get around the rigid specs, provided you can get to someone senior enough to appreciate their value.
Second, even without the promise of new business, a strong enough believer in your abilities who is senior can often get you hired (particularly at lower levels). While this is less true of the government, it holds water even there to some degree.
Third, you may need to trade on the relationships your parents, spouse, or close friends have established. It will have been necessary that you've made a positive impression on the person who could advance your case, but you could essentially be riding on the strength of the relationship others close to you have with the key influencer. (Again, this will apply more to junior level positions than to senior).
FInally, almost two years ago I posted to my blog a piece on likeability ("You'll Only Get Hired If They Like You"):
That piece refers primarily to being liked by the company/organization and people at your potential new employer's, but in a broader sense likeability is a key attribute for career advancement anywhere. A good LinkedIn connection, or an employee with whom you worked for a few years and now has an important job in a firm that you're interested in, is likely to go out of their way to push your case or, at the very least, be willing to spend some time strategizing with you and suggesting people and places you should pursue.
It's been said that the average person can only maintain relationships with about 150 people (meaning relationships that involve a lot more than once-a-year birthday cards or drinks at a 20th college reunion). Make it a point to include some key work contacts (past and present) on your relationship list, and make a genuine effort to cultivate relationships with them, perhaps through a game of golf once a year, dinner with a group "from the old days," an invitation to a play or a Nascar event, a few e-mails with good gossip or good jokes (go easy on the jokes) or a decent size Christmas basket. And, lastly, approach the relationship building and cultivation through the "Win / Win" window. It may not be immediately clear how you will "pay back" the favor that a good connection does for you, but keep the principle in mind and look for opportunities to reward the person who gave you the boost.