One of every five registered voters will share how they voted online, according to a new report by the Pew Internet & American Life Project. The report, "Social Media and Voting," also found that nearly a third of registered voters have been encouraged to vote one way or the other by contacts on Facebook or Twitter -- a number that rises among voters under 30.

If that sounds like a lot of tweets and Facebook posts, you're right. The word "election" has appeared in more than 1.5 million tweets today alone, according to Topsy, and in the past 24 hours, both President Obama and Mitt Romney's names have been tweeted several million times. The Twitter popularity of the presidential debate in Denver -- 10 million tweets in 90 minutes -- even has some pundits speculating that today's election could be the most-tweeted event of all time.

On Facebook, 2.8 million people in the United States have shared they're voting today,  and the number is climbing. (See Facebook's map tracking voter's posts here).

There's some danger in public posting. At the extreme end, All Things D reports photographing your ballot could land you in jail. Less troubling, it could annoy your friends and family.

If you're on the receiving end of too much #electionday chatter, several plug-ins let you mute noisy tweeters or topics for a designated length of time. Mute Tweets and can both hide specific users until the polls close; Chrome browser extensions like PBTweet will also let you do this, among a host of other things. Proxlet, another Chrome extension, can also filter out hashtags and topics of your choice. (Try #election2012, #obama or #romneyryan2012.) If you use Tweetdeck, you're in luck: A filter function is built into the tool's settings.

Facebook isn't quite as easy; your best bet is unfollowing posts from particularly chatty friends. If you're seeing a lot of notifications from a political post you liked or commented on earlier in the day, you can also hide those. Click on the post date, and an option to "unfollow post" will appear at the bottom of the box, next to "like" and "comment."

No matter what you do on social media, though, don't expect to avoid political discussion entirely. While the Pew report found an increase in election day social media sharing, the most popular way to talk politics is still face-to-face. More than half of Pew's respondents said someone had tried to persuade them to vote for Obama or Romney in person in the past 30 days.