Republican Donald Trump edged closer to winning the White House with a series of shocking wins in battleground states such as Florida and Ohio on Tuesday, rattling world markets that had counted on Democrat Hillary Clinton defeating the political outsider, reports Reuters.

With investors worried a Trump victory could cause economic and global uncertainty, investors fled risky assets such as stocks. In overnight trading, S&P 500 index futures fell 5 percent to hit their so-called limit down levels, indicating they would not be permitted to trade any lower until day-side trading resumed on Wednesday morning.

Mexico's peso plunged to its lowest-ever levels as Trump's chances of winning the presidency increased. Concerns of a Trump victory have weighed heavily on the peso for months because of his threats to rip up a free trade agreement with Mexico and tax money sent home by migrants to pay to build a wall on the southern U.S. border.

Trump surged to wins in Florida, Ohio, Iowa and North Carolina, and Fox News projected a win for him in Wisconsin. With voting completed in 49 of the 50 U.S. states, he also narrowly led in Michigan and New Hampshire, edging him closer to 270 Electoral College votes needed to win the state-by-state fight for the White House.

Shortly after Fox called Wisconsin for Trump, supporters at his election evening rally in New York began to chant "lock her up" - a common refrain on the campaign trail for the former U.S. secretary of state repeatedly dubbed "Crooked Hillary" by the volatile Trump.

A packed crowd in the lobby of Trump's new hotel in Washington D.C. chanted "lock her up" and "USA, USA, USA" as state after state was called for Trump.

Clinton still had ways to reach 270 electoral votes, but she would have to sweep the remaining battleground states including Pennsylvania, Michigan and pull off an upset win in Arizona.

As of 12:25 a.m. EST, Trump had 244 electoral votes to Clinton’s 215, with U.S. television networks projecting the winner in 42 of the 50 states and the District of Columbia.

Trump captured conservative states in the South and Midwest, while Clinton swept several states on the East Coast and Illinois in the Midwest. Clinton won Nevada and Virginia.

At 8:55 p.m. EST, Clinton, 69, acknowledged a battle that was unexpectedly tight given her edge in opinion polls going into Election Day.

She tweeted: "This team has so much to be proud of. Whatever happens tonight, thank you for everything."

A wealthy real-estate developer and former reality TV host, the 70-year-old Trump rode a wave of anger toward Washington insiders to challenge Clinton, whose gold-plated establishment resume includes stints as a first lady, U.S. senator and secretary of state.

Both candidates had historically low popularity ratings, although Trump's were worse than Clinton's, in an election that many voters characterized as a choice between two unpleasant alternatives.

Before Tuesday's voting, Clinton led Trump, 44 percent to 39 percent in the last Reuters/Ipsos national tracking poll. A Reuters/Ipsos States of the Nation poll gave her a 90 percent chance of defeating Trump and becoming the first woman elected U.S. president.

Also at stake on Tuesday was control of the U.S. Congress. Republicans will maintain their six-year control over the House of Representatives, major TV networks projected, and were on track to defend their Senate majority, as well, against a handful of failed Democratic challengers.

Republican control of Congress would give the party a strong chance of enacting much of Trump's agenda, if he won the presidency.

In a presidential campaign that focused more on the character of the candidates than on policy, Clinton and Trump accused each other of being fundamentally unfit to lead the country.