Trump shredded Clinton's electoral firewall

Hillary Clinton
Melina Mara | The Washington Post | Getty Images

One reason Hillary Clinton was thought to have an electoral firewall in 2016, is that President Barack Obama twice won Florida, Ohio, Iowa, Wisconsin, Michigan and Pennsylvania.

Clinton has either lost or is locked in a too-close-to-call contest in all of them.

A heavy favorite heading into Election Day, the Democratic nominee suffered a stunning defeat due to an inability to hang onto many key battleground states.

Republican Donald Trump has been declared the victor in Florida, Ohio, Iowa, Wisconsin and Pennsylvania. Michigan has not yet been called by NBC News.

Trump currently has 278 electoral votes, according to NBC, more than the 270 needed to win.

Both candidates spent much of their last few days crisscrossing the key swing states.