Reporters covering this year’s election season in America have found a new form of entertainment: the regular exchange of opinions by President Obama’s chief advisor David Axelrod and Republican candidate Mitt Romney’s advisor Eric Fehrnstrom on Twitter.

One of these exchanges began when Axelrod reacted in his tweet to the claim of Romney’s staff that more Americans have lost their jobs under Barack Obama than under any president before him. “A picture’s worth a thousand misleading words. This chart tells the story,” reacted Axelrod, whose tweet linked to official statistics indicating that, over the last 22 months, the economy has slowly but surely restored jobs lost in the recession. “Sometimes you don’t need a picture to tell a story. The numbers speak for themselves — 1.7 million jobs lost under Obama,” countered Fehrnstrom.

The whole tweeting game lasted several hours before Axelrod closed with the tweet: “Dude, none of my business, but shouldn’t you be in debate prep instead of trying to explain yourself to me?” Which seemed like an appropriate dig. The debate Axelrod had in mind was one in which Romney received a thrashing from Newt Gingrich, and he lost the South Carolina primary a few days later.

The Medium of First Reaction

More importantly, however, the shootouts between Axelrod and Fehrnstrom demonstrate that Twitter has become an important phenomenon in this year’s presidential campaign. All campaign staffs (with the exception of Ron Paul’s) systematically use Twitter to address and influence the public. For instance, when Newt Gingrich indirectly labeled his thoughts “grandiose” in one debate, Romney’s staff sent out a tweet with the tag “grandiosenewt,” encouraging Twitter users to make tongue in cheek comments aimed at Gingrich.

For journalists, Twitter has become something of an “instrument of immediate reaction,” tweeting their quick observations online directly from campaign rallies — or perhaps it is better to say “live.”

For the campaign teams it means that it no longer suffices to analyze TV and press reports, but that they must also treat Twitter as a news source. Members of Romney’s staff, for instance, admitted to The New York Times that they carefully follow journalists’ tweets. For every one of Romney’s appearances — be it a campaign rally or a debate — his staff gathers tweets from media representatives, evaluates them and uses them to try to predict how things will be reported in the official media.

Romney strategist Stuart Stevens told The New York Times, “You can just follow the reactions. It’s basically a focus group.” And it’s not just a matter of following Twitter passively. Staffs try to immediately prepare their own message in response. So, when journalists at a Romney rally in South Carolina tweeted a question from the public on Romney’s Mormonism, it was a signal to his campaign staff to prepare the candidate for the likelihood that this issue might appear at the next press conference.

Your Tweet Ain’t Cool

It is also quite common for staffers to tweet journalists to correct actual or supposed mistakes and inaccuracies, or even to try to brief them that a certain tweet wasn’t the least bit “cool.”

Some media analysts have thus pronounced this year’s contest for the White House as the “Twitter elections,” which is a bit exaggerated: Televised debates continue to be key for the course of the entire bout. Nonetheless, thanks to Twitter, the constant “24-7” cycle created by cable TV and the Internet has become even denser — with the addition of 140-character messages.