When bike-sharing program DecoBike made its Miami Beach debut in early 2011, the concept was novel and the skeptics numerous.

An eye-opening 1.8 million rides later, its blue-and-silver bikes and solar-powered kiosks are part of the seaside city’s landscape, disbelievers are harder to find, and the idea of checking out a bicycle for an errand or a short jaunt across the Beach seems utterly unrevolutionary.

Now DecoBike is poised to expand from its Beach-head into mainland Miami under a deal that backers say could prove an equally potent game-changer for that city’s notoriously auto-centric transportation landscape.

If the Miami City Commission approves a contract with DecoBike, which won a competition to launch a city bike-share service, the private company will install at least 50 rental stations and make 500 bikes available from the Design District south through Wynwood, downtown and Brickell all the way to Coconut Grove. The commission will vote on the deal Jan. 24.

By placing rental kiosks at dense residential and work nodes, entertainment hot spots like Midtown Miami and Mary Brickell Village, as well as near PeopleMover and Metrorail stations, DecoBike and the city hope to establish a connected, alternative transportation system that could finally make getting around Miami by bike and public transit an easy option for many more people.

“I think it will begin to transform how people think about getting around Miami,’’ said Collin Worth, the city’s bicycle planner. “With the ability to get around all that traffic without worrying about gas or parking, especially in congested areas like Brickell Village, this could be the next big thing.’’

Miami’s DecoBike program would be supported by rental fees, memberships and advertising and would receive no public money. The rental kiosks would have ads similar to those on bus shelters. As on Miami Beach, the kiosks would typically be installed in on-street parking spaces.

The program would build on an expanding city network of designated bike lanes and the growing local popularity of cycling as transportation, especially among the young professionals and hipsters moving into the city’s urban core in droves. The monthly unsanctioned Critical Mass ride, which began as a demonstration for cyclists’ rights, now routinely hits 2,000 participants.

They include Miami Heat stars Dwyane Wade and LeBron James, who caused a minor stir recently when he told a reporter he regularly commutes by bicycle to AmericanAirlines Arena from his Grove home.

The bike-sharing concept has spread around the globe since the first program was established in Lyon, France, in 2005. Since then, major cities like Paris, London and Montreal have established wildly successful schemes that have brought tens of thousands of bicyclists to crowded urban streets once fully dominated by motorized vehicles.

“Once people see it and try it, it can change an entire city,’’ said DecoBike chief operating officer Bonifacio Diaz.

The programs provide sturdy, easy-to-pedal bikes that can be rented inexpensively with the swipe of a card from one station and returned at another, making them convenient for short rides to work, the bank or a restaurant.

DecoBike has also benefitted from the remarkably rapid adoption of bike-share programs around the United States. The high Beach ridership figure has made DecoBike the biggest program in the country along with the Washington, D.C., area’s Capital Bikeshare, and turned it into a competitive bidder for new programs in other cities.