Americans face the serious possibility of a Donald Trump presidency, with the businessman highly likely to be the Republican candidate to lead the country following primary elections on Tuesday, a top political consultant has told CNBC. Trump is the projected winner of Republican primaries in Virginia, Georgia, Tennessee, Arkansas, Massachusetts, Vermont and Alabama, NBC News reported on Wednesday. The caucuses in Alaska have yet to be decided. "It isn't over by any means but Trump is coming very close indeed to being the inevitable candidate now … He is well ahead in many of the opinion polls," Alastair Newton, head of Alavan Business Advisory and former political analyst at Nomura, told CNBC from the Global Financial Markets Forum in Abu Dhabi. With Trump as the Republican presidential candidate, the Democrats would face a challenge, said Newton.



Republican presidential candidate Donald Trump waves to the crowd after a rally March 1, 2016 in Louisville, Kentucky. Getty Images

The Democratic Party's Hillary Clinton won in seven states — Virginia, Tennessee, Alabama, Georgia, Arkansas, Texas, and Massachusetts — but fell to rival Bernie Sanders in Vermont, Oklahoma, Minnesota and Colorado.

"Trump is getting people to the polls that historically have not gone. Mrs Clinton is going to have a fight on her hands… It has defied all the pundits today — me included I have to admit … He has certainly proved to be a doughty opponent," Newton said. Republican Senator Ted Cruz, meanwhile, won Oklahoma and his home state of Texas, NBC projected. Senator Marco Rubio of Florida was the projected winner of the Minnesota Republican caucus. Trump's success has surprised people both inside and outside the U.S. and some, such as former U.K. prime minister, Tony Blair, have expressed concern.