At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga.
Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.
Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
It's generally acknowledged that the lessons the Democrats drew from Bush v. Gore is that it matters whether you have one of your guys in the state Secretary of State office, the person who oversees and certifies state election returns. The Democrats generally believed Katharine Harris, then the Florida Secretary of State, and a Republican, threw needless roadblocks in the path of their request for a recount in some south Florida counties, and that if they had had one of their own in that office (or as they would say someone "neutral") the count would have gone forward with a result more favorable to Gore, perhaps providing him with the margin of victory to take the state, and hence win the election.
Since that time, the Democratic Party has pushed for election of strong Democrats to state Secretary of State positions, and opposed the election of Republicans. I believe they succeeded in Minnesota, and were gratified that this allowed them some advantage -- well, they would say "leveled the playing field" -- in the recounts surrounding the very close election in which Al Franken becames the latest (Democratic) Senator from Wisconsin.
The Republican Party generally took away two impressions, first that the Democrats will cheat by demanding recounts of doubtful ballots, perhaps even finding "uncounted" ballots that are not very likely to be legitimate. There was the famous "dimpled" and "hanging chad" questions -- whether a ballot that had no punch-out for Gore, but just a dimple over the dot, where one might guess a voter may have intended to vote, but either (1) made a mistake or (2) changed his mind, and whether to count that as a vote for Gore or not. Republicans felt only a clear and unquestioned vote should be counted, Democrats argued the voters intent should be attempted to understood. The Republicans thought this was cheating, since the only place this "intent" would be attempted would be in heavily Democratic precincts. The saying has arisen in Republican circles that it's necessary for the Republican candidate to win by at least 5%, because "if it's not close, they can't cheat."
The second impression is that the media will attempt to sway the election in the favor of Democrats if they possible can. In 2000, the major networks "called" Florida for Gore before polls closed in the "Panhandle" region of Florida -- which is heavily Republican. The argument is that they did this in an attempt to convince western Florida voters there was no point in going to the polls, that Gore had already won the state, because they knew the actual result was going to be very, very close, and even a few thousand votes out in the Panhandle could swing the election either way.
There is good evidence that "calling" the state for Gore certainly did reduce voter turnout in Western Florida, but the evidence that this the result of a conscious decision by the media is not present. Perhaps they just made a mistake, even if it was perhaps a mistake they really were primed to make, because they really wanted Gore to win the state, and hence the election. It's very hard to know. Similar arguments have been made about polls during this election (2012). Almost all of the polls that show President Obama with a significant lead have party compositions that strain credulity -- e.g. they correspond to the United States having far more Democrats and far fewer Republicans than it did even in 2008, a year of Democratic election blowouts. Many Republicans suspect the polling organizations, who are mostly paid by media organizations, of either skewing their data, or at least not correcting for what seems like weird demographics in their polls. Pollsters respond by saying they just call them like they see them. The net result is that trust in the way the media report the election, from polls to "calling" a state, has sunk, among Republicans, to deep lows. Generally speaking, if the major networks reported the Sun rising in the East, most Republicans these days would still need to go outside to check for themselves.
In short, the general results of the very close election, and the rancor that surrounded the recount and the involvement of the courts, has led to a significant reduction in the trust with which each party views the other, and with respect to which at least party views the media. Whether this is unprecedented is unclear: many times the US electorate has been pretty bitterly divided, e.g. 1800, 1860, 1938. Whether 2000 or 2012 rises to that level is a good question.