This has been the year of the big media gaffe.

NBC News edited a 911 tape of George Zimmerman in a way that implied race as a factor in the Trayvon Martin shooting. CNN and Fox News falsely reported that the Supreme Court had struck down the individual mandate at the heart of the Obama administration’s health care law. ABC News wrongly suggested a link between a mass shooting in Colorado and the Tea Party. Just last week during the storm, CNN repeated a false rumor about flooding at the New York Stock Exchange.

Now the media are gearing up for election night, the finale of the year’s biggest story. It’s a chance to regain some credibility — presuming, of course, that television networks and other news organizations get their state-by-state projections right. They all say they will, still mindful of the mistakes made in 2000, when the networks prematurely called Florida for Al Gore and then George W. Bush.

The same precautions that were put in place after 2000 will be in place again this Tuesday. At NBC, for instance, the statisticians at the “decision desk” that makes projections “are literally sealed off from the rest of us,” said Mark Lukasiewicz, the senior vice president of specials for NBC News.

Different this time will be the level of noise on the Web, where armchair and professional pundits alike will react to the election results in real time. On election night in 2008, a few Web sites, including Slate and Time.com, stated the obvious — that Barack Obama was going to win the presidency — well before the TV networks and major newspapers said so. In large part that’s because the networks and newspapers were waiting for the polls to close on the West Coast.