Now that it looks both Donald Trump and Hillary Clinton have secured their party's nomination for the presidential seats, the clash between the these two candidates is set to be brutal.
American politics is likely to be dominated by the race to presidential seat of Barack Obama in the White House until election day on 8 November.
Follow our poll tracker to keep on track on who's top. It takes an average of the last five polls published on RealClearPolitics.
ON 19 May 2016 was the first time that Donald Trump pulled ahead of Democrat Hillary Clinton in the average of national polls. He was, on average, 0.2 percentage points ahead of Clinton on May 22.
So Clinton had held a lengthy double-digit lead over Trump, who was once a Republican outsider - but this has now vanished.
Trump's polling has previously drawn close to Clinton's during last Oct, as his appearance on Saturday Night Live coincided with Clinton facing pressure in a trial on the deaths of four Americans in Libya in 2012.