Kansas City, Mo. ? When the Power and Light District opened here last year, developers of the upscale eating, drinking and entertainment venue had a vision: Make the several-block downtown area a place where all establishments would be smoke-free.

As of this month, the whole city has followed suit.

Like a growing number of cities and states throughout the country, this fast-changing Midwestern city known for gritty jazz and tangy barbecue has outlawed smoking in all restaurants and bars. The ban, which will begin within two months, comes after citizens voted 52 percent to 48 percent in favor of the ordinance.

The smoking ban places Kansas City, which has in recent years put on the full-court press to become a top tourism destination in the Heartland, in company with other big Midwest cities such as Chicago, Minneapolis, Omaha and Indianapolis.

And just up Interstate 35, the Iowa Legislature this month voted the same way Kansas City residents did: to make Iowa, including the capital city, Des Moines, smoke-free by this summer. (The vote makes Iowa the 24th state to pass a smoke-free law that includes restaurants and bars. In January, Illinois’ statewide ban went into effect.)

The Kansas City ordinance was largely citizen-led, a clear rebuke to a City Council measure that took effect in late March. That measure allowed smoking in bars at all hours and in restaurants with liquor licenses after 9 p.m.

“This was not a government initiative but a citizen one,” said City Council member Cathy Jolly. “The people of Kansas City voted to protect their own health, and that is very exciting.”

Jolly, a breast cancer survivor, is an ardent supporter of the ban, saying she backed it in part to “protect her 4-year-old son, not only now but when he’s 25 years old and at a bar having a beer and watching a ball game.”

Not everyone is embracing the new law. Members of the Kansas City business community who vigorously opposed the ban put forth the same arguments that have arisen in most municipalities and states where similar laws have been proposed or passed.

Their fear, in a nutshell, is that the ban would slash business; bars particularly say customers will go elsewhere if they can’t have a beer and a smoke at the same time. The worries are not unfounded in a state where it is estimated that some 25 percent of the population smokes.

Such numbers have discouraged statewide bans in both Missouri and neighboring Kansas.

Critics are especially livid because two of the city’s major sports venues, the Kansas City Chiefs’ Arrowhead Stadium and the Royals’ Truman Sports Complex, are not covered by the ban. Also exempted are the city’s casinos.

Even more, North Kansas City, a separate municipality, and Kansas City, Kan., just across the Missouri River, still allow smoking in bars and restaurants.