Construction crews hang part of the set for Monday's debate between Hillary Clinton and Donald Trump on Sept. 24 at Hofstra University in Hempstead, N.Y. | AP Photo Poll: Clinton and Trump in dead heat heading into first debate

HIllary Clinton and Donald Trump are virtually tied heading into their first debate, according to a new Washington Post-ABC News national poll .

Among likely voters in a four-way race, 46 percent would choose Clinton and 44 percent would back Trump, while 5 percent prefer Libertarian nominee Gary Johnson and 1 percent support the Green Party’s Jill Stein.


Among likely voters in a two-way race, Clinton’s advantage is the same: She leads Trump by 49 percent to 47 percent. Among registered voters, Clinton and Trump are tied.

A majority of voters expect Clinton to win Monday's debate, the first of the presidential general election, at Hofstra University on Long Island -- 44 percent to Trump's 34 percent. Nearly eight of 10 voters say they plan to tune in.

The poll indicates a tightening race as Trump consolidates the support of the Republican Party and Clinton recovers from a bout of pneumonia and several damaging news stories.

Only 52 percent of registered voters agreed that Clinton is in "good enough overall health to serve as president," while 73 percent said the same of Trump. However, 63 percent said Clinton was "justified" in keeping her pneumonia diagnosis private until she nearly collapsed outside of a 9/11 memorial ceremony in lower Manhattan.

On the positive side for Clinton, President Barack Obama's approval rating remains strong, though it has declined slightly from 58 percent in the last poll to 55 percent now.

In the previous Washington Post/ABC News national poll, conducted in early September, Clinton led Trump by 5 percentage points among likely voters. In August, that lead was 7 points.

Polling averages show Clinton with a lead in the low single digits, with RealClearPolitics showing her ahead 3 points, HuffPollster 4.3 points, and FiveThirtyEight 2.1 points.

POLITICO’s Battleground States average shows Clinton likewise ahead by 3.7 percentage points, using an average of the five most recent reputable polls in 11 swing states. Recent polls in Pennsylvania and Virginia have similarly shown Clinton's lead eroding.

The Washington Post/ABC News poll was conducted from Sept. 19 to 22, surveying a random sample of 1,001 adults by landline and cellphone. The registered voter sample is 834, with a margin of error of plus or minus 4 percentage points; the likely voter sample is 651, with a margin of error of 4.5 points.