Steve Jobs simultaneously led two companies, Apple and Pixar, as chief executive. Elon Musk is running Tesla and SpaceX. Now more people are saying that Jack Dorsey can permanently run two companies at the same time, too.
Mr. Dorsey, 38, is the chief executive of Square, the mobile payments company that has quietly filed for an initial public offering. He is also the interim leader of Twitter, the social media company that he co-founded and that is searching for a new chief. While Mr. Dorsey has long been mentioned as a candidate, one hurdle to his getting the job has been the perception that he is too overloaded because he is also managing Square.
Some Twitter investors and Square investors are now publicly proclaiming that Mr. Dorsey is the right man for the job — both of them.
He will not be distracted by running two tech companies at the same time and can juggle the work, they said.
“After watching Jack execute on his vision at Square, and more recently at Twitter as C.E.O., we are highly confident in Jack’s ability to serve as C.E.O. of both companies,” Justin Dini, a spokesman for Rizvi Traverse Management, said on Monday. Mr. Dini said the firm not only had faith in Mr. Dorsey but also continued to invest in Twitter because of its belief in Adam Bain, Twitter’s president of global revenue.
Rizvi Traverse’s support for Mr. Dorsey is significant because the investment company, which is run by Suhail Rizvi, a famously private investor, was Twitter’s single largest outside shareholder at the time of the company’s initial public offering in 2013. The 15.6 percent stake that Rizvi Traverse held in Twitter has shrunk to less than 5 percent after the firm disbursed Twitter shares to its individual investors, but it remains a big investor in Square.
Rizvi Traverse joins a vocal group calling for Mr. Dorsey to permanently run Twitter and Square. Chris Sacca, an early Twitter investor, has repeatedly pushed Twitter’s board to name Mr. Dorsey as chief executive. Keith Rabois, a venture capitalist at Khosla Ventures, which is a significant shareholder of Square, said Mr. Dorsey could definitely run the two companies simultaneously.
“Deion Sanders played in both the World Series and the Super Bowl,” said Mr. Rabois, referring to the 1980s and 1990s National Football League and Major League Baseball player. “I don’t see any reason why Jack can’t do that.”
It is not a certainty that Mr. Dorsey will get the Twitter job, said two people with knowledge of the discussions, who spoke on condition of anonymity. Still, other investors are saying they won’t stand in the way of Mr. Dorsey taking both jobs. “I think Jack’s the founder of both companies,” Roelof Botha, a Square board member and Sequoia Capital venture capitalist, said in an interview with Bloomberg Television last week. “I don’t think it’s for me to judge, for me to tell him not to do that.”
Jim Prosser, a spokesman for Twitter and its board, declined to comment for this article. Aaron Zamost, a Square spokesman, also declined to comment. Mr. Botha declined to comment on his remarks.
The investor declarations backing Mr. Dorsey as chief executive of Twitter and Square increase the pressure on Twitter’s board, which said in June that it would consider only candidates for the job “who are in a position to make a full-time commitment to Twitter.” The statement would seem to have ruled out Mr. Dorsey, who had said that he did not plan to step down as Square’s chief executive.
While Twitter’s board was initially mixed about Mr. Dorsey’s returning to run the company, some board members are warming to the idea, according to three people with knowledge of the board’s discussions, who also spoke on condition of anonymity. That has put the board in something of a bind because if directors reverse their position and pick Mr. Dorsey, it could make Twitter vulnerable to shareholder lawsuits from anyone claiming to have bought the stock based on the assurance that the company would have a chief who was fully committed to it.
Twitter has also hired the executive search firm Spencer Stuart to compile a list of possible candidates. Some of them have included Beth Comstock, vice chairwoman of General Electric, according to two people with knowledge of the situation, who spoke on condition of anonymity. Consideration of some of these candidates has not escalated into serious negotiations, they said. Ms. Comstock previously led G.E.’s business innovations unit and was promoted to vice chairwoman this month. G.E. declined to comment.
Twitter board members who remain concerned about Mr. Dorsey’s ability to run both companies may well be aware that he is entering an especially busy period. Mr. Dorsey is likely to soon begin pitching Square to public market investors at an I.P.O. road show, and a public offering is expected before the end of the year, according to two people knowledgeable about the situation.
Three months is not an unusual length of time to be seeking a new leader; it took Microsoft about six months to appoint Satya Nadella as chief executive last year, after the resignation of Steven A. Ballmer.
Still, some analysts said investors were growing impatient with Twitter’s process, especially as the company continued to grapple with challenges. Many advertisers are waiting to commit additional marketing dollars to Twitter until a permanent leader and strategy are in place, said Robert Peck, an Internet analyst with SunTrust Robinson Humphrey.
Last week, analysts at Citi Research slashed their advertising revenue estimates for Twitter and downgraded the stock to high risk. Twitter shares closed Friday at $25.29, below the I.P.O. price of $26.
All of this has helped spur some of the public declarations for Mr. Dorsey.
“The public shareholders just want to see this move along here,” Mr. Peck said. “Investors have come to terms with a C.E.O. of Twitter that is also a C.E.O. of someplace else, whereas that wasn’t the case a few months ago.”