Donald Trump victory party on

 Euphoric Donald Trump supporters transformed into a sea of "Make America Great Again" hats, shouting "USA" and partying late into the night as the billionaire appeared within reach of victory Wednesday.

"We are so excited," said Aliza Romanoff, a well-dressed, articulate and educated mother of two from Long Island whose family has known Trump for years, out celebrating with her parents and husband.

The Republican nominee's official "victory party" in a Manhattan hotel ballroom started slowly -- initially quietly optimistic -- but as Trump won state after state, increasingly pumped up and raucous.

The crowd swelled in number, flagging energy levels boosted by alcohol and the avalanche of results that some admitted were far better than they ever imagined with Hillary Clinton the strong favorite.

"It's unbelievable. I didn't know Trump was really going to pull it off," said Glenn Ruti, a 54-year-old New Yorker who works in telecommunications, albeit with no winner yet declared in the race.

"I think he's going to go all the way."

As Fox News, the TV network of choice for most Trump supporters beamed across the party on giant screens, declared Ohio, North Carolina, Florida, Iowa and Wisconsin for Trump, they broke out into whoops and cheers, clapping their hands, fist-pumping and waving placards.

"He's going to win and my life is forever changed," one supporter yelled into his cell phone, seemingly unable to believe it.

Bar staff in black tie rushed around collecting empties or bringing out fresh bottles. There were spontaneous chants of "Drain the Swamp." That is Trump's battle cry for overhauling establishment Washington.

"We're definitely taken aback. We were expecting it to be a very close race," said Romanoff. "We're overjoyed," she added as her mother promised a month of partying all the way to the inauguration on January 20.