Easy Solution: Change the URL
The solution is very easy, most of you know this I am sure, but I saw no one saying this in their posts or comments about how they had giving up hope on a particular blog post. If it gets submitted and goes no where, then change the URL, 301 Redirect the old URL and then submit it through a decent account. If you story gets 70 Diggs and is 5 articles from the front page on Up and Coming and doesn't make it then you may be screwed, as a lot of people will have seen it and you will get buried for trying again. It can work though, you just wait long enough and vary the title and description :). If the story goes to the land of "One Voters" then resubmit it right away and reap the benefits. As your blog grows in readers this will happen more and more, just know that on the super premium content you don't have to give up hope.
I don't care what you say there is one thing that is an absolute about promoting content on social sites, and that is if you don't have a good account with others watching your submissions, you will get nothing to the front page. The only exception would be you if the blog you submit is very popular with thousands of active readers, and they had the Digg this button on the site after you submitted it, enabling the readers to vote it from the site instead of on Digg or any others. It wont go popular on Digg or Reddit unless there are others to Read it and vote. The content has to be given the chance to be voted and if there are no friends watching or the story doesn't make Hot in Up and Coming in its category then no one will see it.
Now StumbleUpon you can get by with a lesser account as the submission will get put in front of some people through the tool bar but if you are a lesser account it will need the Thumb Up of a power user or two in order to gain the traction you want. What can happen in SU like in the link int he first paragraph, is most people that are starting out don't know how to use the category tags the right way. This will destroy a good submission. What usually happens is they go super quick and use a suggestion from SU on some super competitive tag, or they don't think about the real content and submit it to a not so popular category.
One tip you can do at SU is if you have your own site, submit it then watch the traffic, and if it isn't that good (in the hundreds) then edit your submission and switch some tags and categories and see if it improves. Rinse and repeat and you can get a good idea of what works. We once submitted a story on a blog related to surfing but about Eco-Friendly stuff, it was originally submitted to the surfing category, got maybe 150 visits in two days, we switched it to environment, and it exploded, new subscribers, comments, links and thousands of visits.
If you have a lesser account work on building up a trusted network of friends before submitting, then start with high profile news sites etc to test out your account. This way you will build your account faster and won't burn the blogger trying to make a living from home in the meantime.
*Edit: I have been getting some hate on this from people that say they have "lesser" accounts at social sites. This post is not to rag on someone with an up and coming account. Everyone starts out with a junk account. This post if for content writers who unfortunately might have someone with no friends submit their stuff to social news, where it stays at one vote for its entire life span.
This is also not tips about submitting duplicate content, is it really duplicate content if no one but the submitter reads it?