And many advertisers, analysts and investors say Twitter already has the right person for the job: not interim CEO Jack Dorsey but Adam Bain, the company's president and head of revenue, who has emerged as an early favorite.

Twitter's outgoing chief executive, Dick Costolo, resigned abruptly Thursday amid pressure from investors to increase the user base and improve what's known as direct response advertising, the most lucrative type on the microblogging site.

Those ads prompt users to take an action, such as signing up for a website or buying a product. Improving them is central to Twitter's ability to make more money.

Before joining Twitter in 2010, Bain served as president of the Fox Audience Network where he was responsible for monetizing advertising platforms across News Corp's  web properties. At Twitter, he has helped aggressively grow the advertising platform. He holds many of the company's most valuable relationship with advertisers and understands the media business, advertisers said, and could help redirect Twitter so it meets advertisers' demands and makes more money.

For now, advertisers hope the management change will "light a fire" under Twitter, said Adam Epstein, chief executive of adMarketplace, which works with search advertisers. Even though they have discussed ways to improve advertising with Twitter executives, the company has been slow to change.