By Monday night, just two days after he started his Twitter account, the 80-year-old chief of News Corp had already issued more than 20 tweets and acquired 74,000 followers.
Teri Everett, a spokeswoman for News Corp, confirmed the Twitter account (twitter.com/#!/rupertmurdoch) was Murdoch's.
Murdoch transformed his father's small Australian newspaper business into a global media conglomerate both admired and reviled for its power and reach. News Corp, whose holdings include The Wall Street Journal and Fox News Channel, was hit last year by a phone-hacking scandal in Britain that led to its closing of the News of the World newspaper.
In one of his tweets, Murdoch described Santorum, a socially conservative former senator who has risen sharply in the polls ahead of Tuesday's Iowa caucus, as the "only candidate with genuine big vision" for the country.
In another tweet, Murdoch said, "Good to see santorum surging in Iowa. Regardless of policies, all debates showed principles, consistency and humility like no other other."
He called Obama's decision on the detention of terrorism suspects "very courageous - and dead right!"
Murdoch also commented on Walter Isaacson's biography of Jobs, the late Apple Inc CEO, tweeting, "Interesting but unfair, family must hate."
In other tweets, he expressed support for films "We Bought A Zoo" and "The Descendants," both from his Fox movie division. He even commented on New York traffic, tweeting, "NY cold and empty, even central park, nice."
It remains to be seen if Murdoch's Twitter foray will pay off in public relations terms. One of his tweets, "maybe Brits have too many holidays for broke country," was deleted, but not before it was captured by other Twitter users and media.
Reuters is a competitor of The Wall Street Journal and Dow Jones Newswires, the financial news agency that News Corp acquired along with the Journal in 2007.
(Reporting by Greg Roumeliotis in New York; Editing by Peter Cooney)
Posted by Jason Lomberg, Technical Editor