WASHINGTON - Donald Trump, the Republican Presidential candidate, is slightly ahead of his Democratic rival Hillary Clinton for the first time in months, according to the latest ABC News/Washington Post tracking poll.

Trump is leading with 46 per cent of likely voters, while Clinton has 45 per cent.

The two candidates are divided by a slim .7 (point seven) percentage point margin, which is well within the poll’s margin of error.

Trump led Clinton in just one other ABC News/Washington Post tracking poll, conducted in May shortly after he clinched the Republican nomination. At the time, Clinton and former Democratic candidate Bernie Sanders were still locked in a primary battle.

The poll—conducted between Oct 27 and Oct 30—surveyed 1,128 likely voters and had a margin of sampling error of plus or minus 3 percentage points.

The RealClear Politics polling average for Oct. 22 to Oct. 31 shows Clinton ahead by a margin of 2.4 percentage points with 47.7 percent support.

According to a Real Clear Politics average of recent polls, Clinton's lead had declined from 4.6 points on Friday to 2.5 points on Monday.

Hillary is losing support among voters after renewed controversy over her use of a private email server while she was head of the US State Department.

FBI Director James Comey told Congress in a letter made public on Friday that his agency was looking into new emails that may be connected to Clinton.

Clinton was investigated by the FBI over her use of the private server and how she handled classified information while she was Secretary of State from 2009 to 2013. However, Comey concluded in July that there was not enough evidence to bring criminal charges against Clinton.

The FBI has revealed very little to the public about the new emails under investigation, except that they were uncovered during an unrelated investigation into former US Congressman Anthony Weiner, the estranged husband of top Clinton aide Huma Abedin.