About 220 million Americans are eligible to vote, but only about 140 million people are expected to cast ballots across the 50 states by the end of Election Day on Tuesday.

But just winning the popular vote will not necessarily send one of the US presidential nominees, Donald Trump or Hillary Clinton, to the White House.

Instead, the complicated US election system requires a candidate to secure a majority of the 538 votes in the Electoral College — 270 or more – in order to win the presidential race.

Both candidates have held rallies in the swing states of Florida, Pennsylvania, North Carolina and Michigan.

Swing states, also called battleground states, are states in which no single nominee or political party has overwhelming support in securing that state's Electoral College votes.

The Washington Post Prediction

The other battleground states in the 2016 election cycle are Virginia, Iowa, Nevada, Ohio, Colorado and New Hampshire.

Clinton has an advantage in the popular vote and can afford to lose in a couple of traditional battlegrounds such as Ohio and Florida.

But is she also loses in other swing states like North Carolina and Pennsylvania, then that could become fatal to her White House ambitions, Press TV reported.

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