BRIDGEPORT — Donald Trump barnstormed through Connecticut’s largest city Saturday, returning to the place where he was thwarted from building a casino two decades ago with a more audacious proposition — the presidency.

The enigmatic front-runner for the GOP nomination strayed from the traditional road map of Republicans in this reliably blue state with a raucous midday campaign rally at the Klein Memorial Auditorium.

But then again, Trump has taken an unconventional path throughout the primary race, which has wound its way from Iowa and New Hampshire to New York and now Connecticut.

It was Trump’s second stop of the day in one the state’s hardscrabble industrial cities, and the billionaire made promises of a jobs renaissance and lamented what might have been if his waterfront casino development had been allowed to advance 20 years ago.

“Real geniuses, they said, ‘No,’ and now it’s dying,” Trump told the packed theater, referring to Bridgeport and its leaders.

Connecticut holds its primaries Tuesday, setting Trump up for a potential sweep of its 28 GOP delegates if the voting mirrors a recent Quinnipiac University Poll giving the real estate tycoon a commanding lead over John Kasich and Ted Cruz.

Gruff and unscripted, Trump harangued the media, Hillary Clinton, Ted Cruz, Bernie Sanders and Karl Rove, the former adviser to George W. Bush adviser who is now a Fox News talking head and has dismissed Trump’s conservative credentials and path to the White House. The Trump faithful, mostly blue-collar types with a few party insiders scattered about, were in all their glory. Some wore T-shirts that read: “Clinton for prison in 2016.”

“It’s not really the Trump phenomenon. You are the phenomenon,” Trump said. “Our crowds are much bigger than Bernie. A month from now, you’re going to say, ‘Who the hell is Bernie?’ Unless Hillary gets indicted.”

The former star of “The Apprentice” was interrupted several times by protesters, who were removed from the building, including one black man who taken away from the lobby in a choke-hold.

Clinton’s campaign declined to comment, but the Connecticut Democrats blasted Trump.

“The bottom line is that Donald Trump’s campaign has been an embarrassment for the Republican Party and for the United States of America,” said Alynn Woischke, executive director of the state Democratic Party.

Trump arrived in Connecticut by helicopter, flying over his one-time mansion on the Greenwich waterfront that’s being listed by its current owner for $54 million and has been on the market for 18 months. His day started in Waterbury, the former brass capital, with a morning rally. In Bridgeport, his supporters started lining up more than three hours before Trump’s splashy entrance.

“If I could talk to him, I would tell him, ‘I’m like you. I take no prisoners,’ ” said Nick “Batso” Maccharoli, 82, a retired auto body specialist from Stratford who is known locally for his full body tattoos and reality television appearances on “Rescue Ink.”

Maccharoli said he has never attended a campaign rally and is not a registered Republican, which makes him ineligible to vote in Tuesday’s closed primary.

“I come to see the man, see what he has to say,” Maccharoli said.

A few rows in front of him, wearing a neatly tailored suit, Charles Glazer, a former Republican National Committee member and top GOP fundraiser from Greenwich, sat.

“Donald Trump is leading the field, and I think it’s important that we all listen to what he has to say,” Glazer said.

There are just 3,800 Republicans in Bridgeport, which has a population 147,612. The theater holds 1,400 people.

“I wish we had a line like this for Republican Town Committee meetings,” said John Slater, the city’s former GOP boss. “Donald Trump is waking up a lot of voters.”

Slater was part of a group of VIPs who met Trump backstage before the rally. The group included House Minority Leader Themis Klarides, R-Derby, who also appeared on stage. The first woman to lead her caucus, Klarides last summer condemned Trump for his comments about women and said Trump was part of the “B team.”

“There’s no perfect candidate. Let’s put it that way,” Klarides said before the event. “Whoever is our nominee, we need to coalesce behind them and work together in taking back the White House.”

Klarides used the spotlight to assail Gov. Dannel P. Malloy and his fellow Democrats in the Legislature’s majority.

“Take your deep hatred for Dan Malloy and put it over here for the next six months,” Klarides told the crowd.

Malloy’s spokesman Devon Puglia lobbed a return salvo at Klarides, who has said she does not intend to vote for Trump in the primary.

“Usually, when people endorse hate speech, they are smart enough not to use the word ‘hate,’ ” Puglia said.

Backstage, Bridgeport’s Democratic Mayor Joe Ganim, whose city is set to host Clinton on Sunday, made a surprise cameo. The second-chance mayor of the state’s largest city could be seen leaving a holding room where Trump had been signing autographs for Republican VIPs.

In the mid-1990s, Trump partnered with Ganim during Ganim’s first stint as Bridgeport’s mayor to push a waterfront casino development in the city. But the project was met with competition from rival casino mogul Steve Wynn and Foxwoods developer, the Mashantucket Pequot Tribal Nation, as well as opposition from politicians such as then-Gov. Lowell P. Weicker Jr. Ganim reclaimed his former office in last fall’s election after serving prison time for corruption.

A request for comment was left Saturday with Ganim’s office.

Outside the theater, Fairfield’s Republican Town Committee chairman, Jamie Millington, helped with crowd control.

“I’ve never seen anything like this,” Millington said. “Often, Connecticut is fairly complacent in these things.”

Jeffrey Wright, a former state GOP vice chairman from Trumbull, recently “lateraled over” from being a Kasich supporter to backing Trump.

“I’m enthusiastic that Donald Trump can change the conversation in the state and the nation,” Wright said.

In the parking lot, Austin Taylor, a traveling vendor from Lubbock, Texas, who has been following Trump around the country and started a clothing line called GOP Jerseys, hawked merchandise.

“I like just kind of the alpha that Trump brings to the table,” Taylor said.; 203-625-4436;