NEW YORK: Billionaire populist Donald Trump was poised for a possible shock victory over Hillary Clinton in Tuesday's historic US presidential election, as a string of swing state victories for the Republican jolted world markets and stunned her supporters.
As polls closed and media called state races one-by-one, giving the key battleground states of Ohio, Florida and North Carolina to the Republican maverick, pollsters scrambled to update their forecasts and point to an improbable upset.
Clinton -- the 69-year-old Democratic former first lady, senator and secretary of state -- began the day as the narrow favorite to win the White House and become America's first female president.
But Trump's string of successes reflected how deeply divided the American electorate has become, and showcased his ability to tap into white blue-collar voters' resentment of cultural change linked to immigration and the loss of manufacturing jobs at home.
World markets plunged as US observers awaited results from the Rust Belt state of Pennsylvania, the northeastern state of New Hampshire, and the northern states of Michigan and Wisconsin -- all now vital to Clinton's hopes.
Mexico's peso plummeted over fears that Trump will make good on his vow to wall off America's neighbor to the south.
Safe haven assets rallied, with the yen and gold rushing higher, and Wall Street futures fell 3.7 percent in after-hours trade. Asian markets were in turmoil, with Indian stocks dropping six percent.
Clinton supporters who had gathered at a glittering reception in New York expecting to hear a victory speech from Clinton fell quiet and jabbed nervously at their phones.
Major donors had tears in their eyes as they stared stupefied at the screens, and an audible gasp filled the room when North Carolina went into Trump's win column.
"Not great," muttered railroad retiree Joan Divenuti, who came all the way from Massachusetts to cheer her heroine. "Florida was always a problem," she added.
Across town at the Trump election party, the 70-year-old property tycoon's supporters -- a more well-heeled crowd than the blue-collar Midwesterners he is counting on for victory -- cheered and pumped their fists at each advance.
"I think we're going to win," said 22-year-old Brendon Pena, who works for a company that leases office space in the soaring Trump Tower.
"I was always positive. I think Donald Trump is a really smart guy. He knows what we're going to do and we're going to win the election."
At 11:30 pm (0430 GMT), Trump was projected to win 24 states worth 229 electoral college votes, within striking distance of the 270 he needs.
Clinton stood at a projected 209 electoral votes.