Microsoft has picked ad agency JWT to oversee an $80 million to $100 million campaign for its new search engine, possibly under the Kumo brand name, according to an Advertising Age report today. The online, TV, print and radio campaign is expected as early as June, according to the report. It appears to be the first time the timing of the potential rebranding has been nailed down.

Whatever the overhauled search engine called, the news suggests that Microsoft is finally moving ahead with its efforts to overhaul Live Search and market it more effectively. Executives have conceded repeatedly that they haven't done enough to build the brand in the minds of consumers, but Microsoft's long flirtation with Yahoo appears to have kept the company from moving forward aggressively on its own.

Meanwhile, Microsoft's share of the U.S. search market fell to a new low in February.

Writes Ad Age: "According to one person close the situation, the forthcoming campaign will be careful to not position 'Kumo' as a competitor to Yahoo or Google and instead cast it as a reimagined search engine that ups the game by yielding fewer but more-focused results."

Will it work? Who knows. But based on where Microsoft stands at this point, it couldn't hurt.

Microsoft declined to comment on the report. We remain convinced that the company's branding challenge -- which is now, by extension, JWT's challenge -- would be significantly less if the company would drop the whole Kumo thing and go with its Start.com address instead. Based on today's report, however, that's not looking likely.