Is a strong Cover Letter with the Resume an important step in getting that “Second Look” from Recruiters Online?

Again being in the recruiting business and high volume recruiting business don't have time to look at the coverlet terms. Focus on the resume and networking so that you get referred to a role. That is where 70% of people at least get a look and possibly an interview

You have to know your audience, industry and company. Cover letters may work well for a smaller company. When I am looking through thousands of resumes for multiple roles I am looking for the meat and the potatoes so I can get candidates over to Hiring Manager for review

Interesting thing is USA Jobs won't allow for cover letters which are typically a bunch of hot air. Prior to USA Jobs, we had the HR side strip the package of cover letters as they were not part of the required submissions that are valid to review.
That said, on the outside, a decent cover letter can't harm, but isn't likely to do much good either. People still do them because they think is slightly better than 50/50. Bottom line, if you're anal about cover letters, your mind is in the wrong place.

As an Account Rep for Bradley-Morris who works directly with Hiring Managers and Corporate HR Reps to place transitioning Military Personnel into the civilian work force. I have yet to supply a cover letter produced by the candidate when I email a resume over for submission. I do however take the time to write a brief introductory email of the candidate clearly and decisively stating why the candidate is a solid fit for the job and what directly transferable skills or experiences they bring to the table.

This email is essentially me telling the Hiring Manager why they should interview the Candidate. Specifically, I want to let the recipient know why this candidate is relevant to the position. I've found this greatly increases the probability that the candidate will get fair consideration for the job opening. It replaces the cover letter from the candidate. However, this email draws upon my relationship with the recipient and my knowledge of the position.

Jobs are normally secured by relationships. Who you know is almost equally as important as what you know. If you have the proper connection, such as a friend who works for the company or knows the hiring manager, make the introduction you will essentially be using their relationship and credibility to get you in front of the hiring manager. They will essentially be vouching for your credentials, which is the intent of a well written cover letter.

My recommendation for a candidate is this. If you have the relationship to get you in the door, a cover letter is most likely not needed. However, if you are applying to a job in which you have no direct connection, you should do anything that you can do to highlight your qualifications for the job and differentiate yourself from the hundreds of other resumes the processor in HR will see and make a 20 second snap judgement on. In this case you should absolutely write a cover letter. Be sure that it is directly relevant to the job you are applying for. It should not contain broad statements such as a I'm a good leader, or stay until the job is done type of stuff. It should contain real meat as to why you are relevant for this job.

I have to agree with CW# Dylan E. Raymond if it's a small company or a unique position then a cover letter draw additional attention to your resume. When I have 80 positions to fill with multiple candidates I head straight to the summary. Your resume is a sales pitch it should grab the recruiter in the first 30 seconds .

I think it all depends on the position. I rarely look at Cover Letters, but if I think the resume is on the fringe of me passing forward I will review ones Cover Letter to see if there is any more "meat" I can pass along to the hiring manager.

http://milewalk.com/mwblog/write-thank-you-that-gets-you-hired/
In addition to a personalized, job-specific cover letter, I strongly encourage candidates to write a personal, hand-written thank you note for an interview. Anything that can differentiate you from another candidate will keep moving your name to the top of the list. Good manners never go out of style!

Not necessarily I do not even look at cover letters

It's been a very long time since I was a recruiter but overall I'd say cover letter was pretty insignificant in our firm. We had screeners who reviewed all submissions before they sent a resume on to the recruiters. Part of their responsibility was to strip off any cover letters, review resume to see if it matched job requirements for positions being worked and pass those that did on to recruiter. At best the cover letter may have caught the attention of the screeners but ultimately it was the quality of the resume that got you looked at. Comments about text and online applications also make sense I have the feeling that cover letters maybe going the way of the dinosaurs except for some very specific situations.

I haven't written a resume since I started working. I was a cook for 9 years prior to coming in the Air Force. I haven't had much reason to write one, but I am going to get started while I am here in Korea COL Mikel J. Burroughs.