Story highlights Donald Trump has a slim one-point lead, his first time ahead in an ABC/WaPo poll since May

Hillary Clinton still leads in the CNN Poll of Polls, an average of the five recent national polls

(CNN) Hillary Clinton and Donald Trump are neck-and-neck in a new national tracking poll out Tuesday morning.

The latest ABC News/The Washington Post offering showed Trump barely edging Clinton among likely voters, 46%-45%, well within the poll's 3 percentage point margin of error. Support for Libertarian Party nominee Gary Johnson, meanwhile has fallen to a new low, according to the poll, plunging to just 3% nationwide. Green Party candidate Jill Stein is at 2%.

Although Trump's single-point advantage over Clinton is statistically negligible, it is his first lead in an ABC/Post poll since May -- perhaps giving hope to the Republican presidential nominee's supporters, who believe their candidate's prospects were bolstered last week with the revelation that the FBI is reviewing new emails found on the laptop of Anthony Weiner, the former congressman and estranged husband of top Clinton aide Huma Abedin.

Still, it may be too early to gauge the electoral impact of that development, which broke on Friday. Clinton still leads Trump in the CNN Poll of Polls, an average of the five most recent national phone polls, including Tuesday's ABC/WaPo tracking survey, 46%-42%.

The latest ABC/Post poll showed a lack of enthusiasm among Clinton supporters. Only 45% of the Democratic nominee's backers say they are very enthusiastic about supporting her, down 7 percentage points since the start of the tracking poll and eight points lower than the share of Trump supporters who say they are very enthusiastic about supporting their candidate.

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