I'll be honest - I've had plenty of posts that have earned nothing. That doesn't seem like it justifies trying again with duplicate content. Your content had its chance to rise and/or fall on its own merits; using excuses like "I didn't have as many followers then" or "there are a lot more users now" or something similar seems like petty rationalization to me.
It does seem motivated by greed, and that's a shame. Yes, let's be honest here, part of the allure of Steemit is the opportunity to earn rewards for your content, but making that your primary motivator for posting here sends the wrong message.