Downtown Cleveland looms beyond the Tremont neighborhood, where old factories and warehouses are quickly being replaced with housing and businesses. (Jabin Botsford/The Washington Post)

When this former industrial powerhouse beat out Dallas, Denver and other cities competing to host this summer’s Republican convention in the same week that basketball legend LeBron James announced his return to the Cavaliers, Cleveland felt it had its mojo back.

Millennials were moving downtown. Lakefront condos, luxury hotels and outdoor cafes were opening around a new convention center, and the Public Square, the heart of downtown, was getting a $50 million makeover with new fountains, lush grass and blooming dogwoods. The “Comeback City” couldn’t wait for Republicans from every state and 15,000 journalists from around the world to check out the change — and spread the word.

But back then, in 2014, no one forecast Hurricane Donald.

Now Donald Trump, the most unconventional presidential candidate in modern times, is promising to create “a big spectacle” with a “showbiz” feel, leaving Cleveland excited about the heightened interest — and nervous about what might happen with the arrival of the political storm.

“I would venture to say we have never had this much attention,” said David Gilbert, president and chief executive of the Cleveland 2016 Host Committee. “In terms of changing the narrative about Cleveland, showcasing all the change, it’s a tremendous opportunity. . . . We are no longer the bridesmaid.”

Photos from the 1924 Republican National Convention can be viewed in the Cleveland Public Library. The Ohio city is preparing to hold its first major political convention since 1936. (Jabin Botsford/The Washington Post)

The last time Cleveland held a convention was in 1936, when Kansas Gov. Alf Landon was handed the Republican nomination here and Franklin D. Roosevelt won the Democratic bid in Philadelphia, the city that will also host this year’s Democratic convention.

In 2012, 30 million people tuned in to see Mitt Romney accept the GOP nomination on the final night of the Tampa convention. TV networks are predicting far more eyeballs on Cleveland. Facebook, Twitter and Google are all preparing for the biggest social-media political event ever held.

“The accessibility of this convention will be unprecedented,” said Audrey Scagnelli, national press secretary for the Republican committee organizing the convention. AT&T just finished laying 50,000 feet of fiber downtown, she said, to “make sure anyone with an Internet connection” in any corner of the world sees what is happening in Cleveland.

Couple global exposure with a “candidate who is a lightning rod” and Clevelanders get nervous, said Christine Link, executive director of the American Civil Liberties Union in Ohio. “It was supposed to be Jeb Bush in a slam dunk, and we were going to have a lovely, beautiful party,” she said, recalling the thinking back when the city landed the convention two years ago.

Now, Bikers for Trump, the ­Coalition Against Trump and a growing list of fired-up groups are applying for permits to march down the streets.

With the GOP convention less than two months away, Cleveland scrambles to prepare for the arrival of tens of thousands of delegates, demonstrators and journalists. The Washington Post's Ed O'Keefe walks us through the latest developments to see where the city stands ahead of the convention. (Dalton Bennett/The Washington Post)

“He’s dangerous to our country!” said Tom Burke, who is coming from Grand Rapids, Mich., to organize an anti-Trump rally. “I am 51, and in my lifetime we have never seen a candidate like this. He talks about using nuclear weapons! He is going to start another war!”

Demonstrators picket every political convention, but there is added security concern here because punches have already been thrown at Trump rallies — including last week in San Jose. Cleveland police have insisted they are prepared for the thousands of people who love Trump sharing the streets with thousands who detest him.

There is already a lot of focus on police because of the 2014 shooting death of Tamir Rice, a 12-year-old who was carrying a toy gun, as well as a Justice Department finding of a pattern of use of excessive force.

Gun rights advocates have started a petition, signed by more than 45,000 people, to allow people to carry firearms at the convention; Ohio, like many other states, has an open-carry law. But the Secret Service is banning guns in and immediately around the arena.

Police officials said officers will wear body cameras — and many will wear shorts and ride bikes or horses in a deliberate effort not to appear confrontational. If officers don riot gear, which is incompatible with the cameras, special police video crews are to accompany them.

A downtown shop displays an image of the man who will be on everyone’s mind next month: Donald Trump. (Jabin Botsford/The Washington Post)

“It’s going to be a zoo. Nobody envisioned it would be Trump coming here,” said Carl Wendorff, a warehouse manager.

Cleveland sought the convention in the hopes of shedding what Gilbert called “a perception problem.”

In other words, people were sick of their city being called the Mistake on the Lake.

It was a way to get thousands of people to see, for instance, paddle boats and pike in a river that was once so polluted it caught fire. That 1969 fire on the Cuyahoga turned the city into a punch line.

Decades of hard times, factory closings and population loss have hurt. But recently, the health-care industry, led by the Cleveland Clinic and University Hospitals; an affordable cost of living attractive to many national firms; and a new effort to market the food, music and art scene helped lead a rebirth.

“I have a two-minute commute,” said Peter Hart, 25, a PNC bank employee and one of the thousands who now live in the heart of the city.

Jeremy Paris recently moved here from Washington to lead a group charged with beautifying downtown. The executive director of the Group Plan Commission stood at the edge of the soon-to-open six-acre Public Square park that will have an outdoor art exhibit in summer and an ice rink in winter.

The Republican convention accelerated many projects. Workers are everywhere installing giant flower planters, paving streets and scrubbing 200-year-old facades. Last week, car chase scenes for the latest “Fast & Furious” movie were being filmed near the city’s lakefront Rock and Roll Hall of Fame, where the convention’s opening-night party will be held.

“You get your house ready for a party — that’s what we are doing,” Paris, who used to work on Capitol Hill, said about all the activity.

The convention is expected to inject over $200 million into the local economy — a key reason so many in this Democratic county, which voted solidly for Barack Obama, don’t mind being overrun by Republicans.

“A barbershop owner was just telling me he has a bunch of Secret Service guys coming in every week to get their hair cut,” Gilbert said.

Hundreds of people are already here spending in big ways and small, he said.

Trump, the longtime owner of the televised Miss Universe pageant and star of the reality TV show “The Apprentice,” said in an interview with The Washington Post that conventions in the past have been too dull. “It’s very important to put some showbiz into a convention, otherwise people are going to fall asleep,” he said.

Trump is even thinking about using the 67,000-seat Cleveland Browns football stadium for a Trump address, a far bigger venue than the convention center. But he is not saying yet what celebrities he is hoping to woo to Cleveland. Notably, many GOP stalwarts, including Romney and former presidents George H.W. Bush and George W. Bush, are staying away.

So are a “small handful” of companies who usually sponsor the event, Gilbert said. In this hyper-divisive election cycle, companies including Coca-Cola are taking pains to say they are not endorsing any candidate and offering the exact same donation to help pay for both party’s conventions.

So far, Cleveland has raised $57 million of the $64 million it pledged to help pay for hosting the event, which is expected to draw 50,000 delegates and media.

On a recent evening downtown, many people jogging and walking talked about the buzz in the Lake Erie air. James and the Cavaliers are in the NBA Finals, and Clevelanders are counting down to the city’s big moment in prime time, which begins July 18.

In this city, used to bad news, many people can’t help but worry something will go wrong.

But Carol Sanders, who works for the local Sibling Revelry Brewing, is getting into the spirit, even offering a special convention beer called Swing State Pale Ale.

To satisfy every political taste, the beer can be poured from either a red tap or blue tap.

A man walks his dog walk toward downtown from Cleveland’s Tremont neighborhood. (Jabin Botsford/The Washington Post)