SAN FRANCISCO -- Google Inc.'s bid to blanket San Francisco with a free wireless Internet service cleared a major hurdle Wednesday when city panel identified the Internet search engine leader and EarthLink Inc. as the best candidates to complete the ambitious project.

The recommendation, completing a six-week review, clears the way for the city to begin final negotiations with Google and EarthLink, which decided to team together earlier this year after initially bidding against each other. The companies will pay to build the entire network, which is expected to cost at least $15 million.

EarthLink envisions charging roughly $20 per month for the ability to surf the Web at speeds four to five times faster than Google's free service, expected to be financed with a heavy dose of ads.

Either way, the wireless, or Wi-Fi service, would be faster than Internet access over a dial-up modem. The Google component of the service would make San Francisco the largest city in the nation with free Internet access throughout its borders.

Philadelphia, an even larger city, is further along in its attempt to provide citywide Internet access, but its service -- also being provided by EarthLink -- plans to charge fees. Other big cities trying to build Wi-Fi services include Chicago and Minneapolis.

Atlanta-based EarthLink technically will take the lead in the final contract negotiations with San Francisco, but Google's involvement is attracting the most attention.

The project has spurred widespread speculation that Google is secretly planning to build a national Wi-Fi network to ensure more people have Internet access so they can view the online ads that accounted for most of the company's $1.5 billion profit last year.

Google has said it's only interested in providing free Wi-Fi in San Francisco, where many of its employees live, and about 35 miles to the south in Mountain View, Calif., where the company's headquarters are located.

The joint proposal from EarthLink and Google prevailed over five other finalists: Communication Bridge Global; NextWLAN; Razortooth Communications LLP; MetroFi; and SF Metro Connect, a partnership that includes SeaKay, Cisco Systems Inc. and IBM Corp.

After reviewing a wide range of criteria, the city's five-member panel ranked the EarthLink-Google package as the best deal for San Francisco, followed by MetroFi and the partnership that included Cisco and IBM, said Chris Vein, the director of the city's technology department.

Vein will now lead the negotiations on a final contract that will cover privacy and security issues, as well as how much the premium service will cost. Once both sides agree to terms, the contract will require final approval of San Francisco's Board of Supervisors.

San Francisco Mayor Gavin Newsom, who first proposed a free Wi-Fi network in October 2004, hopes the service will be up and running before the end of this year. Newsom believes free Wi-Fi will make San Francisco a more appealing place for businesses and help close the so-called "digital divide" by enabling more low-income households to connect to the Internet more easily.

But unforeseen stumbling blocks during the final negotiations and approval process could result in delays, said Greg Richardson, a telecommunications consultant who was one of the panel members who recommended the EarthLink and Google proposal.

The other panel members, whose identities had been kept secret until Wednesday to avoid attempts to influence their decision were: Joseph John, who works for Vein; Hans Loffeld, information technology director for the San Francisco Public Utilities Commission; Brian Roberts, a senior policy analyst for San Francisco's technology department; and Bram Elias, a policy analyst for the San Francisco Public Utilities Commission.