Quick upvotes are huge. /r/CenturyClub and associated reddits for high karma holders make it a hobby of gaming the system. They discuss timing strategies, keywords, follow each other to get quick upvotes, etc. They take karma very seriously. Most of those people are comment karma whores though who just hang out in askreddit/new and shitpost puns and jokes.
Most post karma whores do it through sheer volume. If one in 20 posts sticks that is good enough for them. That is how people like GallowBoob became so popular and now he has so many followers that almost everything he posts gets tons of votes. He only has 4 posts in the last 7 days with less that 1,000 ups and most with far more, up to 100,000+.
My one "top link of the day" was posted at 7 p.m. PST so only had 5 hours to get votes. Bad timing. But is was about the first federal court of appeals decision that taping of police with your cellphone was legal. Very sexy keywords for redditors.