Donald Trump trails Hillary Clinton 51 percent to 39 percent in the latest Washington Post/ABC News poll conducted last week. UPI File Photo
WASHINGTON, June 27 (UPI) -- Three weeks before the Republicans' convention in Cleveland, Donald Trump's support is declining, according to a new Washington Post-ABC News poll.
The presumptive GOP nominee trails probable Democratic nominee Hillary Clinton, 51-39 percent, in a poll conducted last week. Last month, Clinton's lead was only 2 percentage points (46-44). It's also Clinton's largest lead
since last fall in Post-ABC polling.
When third-party candidates are included, Clinton's lead drops to 47-37 with Libertarian Gary Johnson at 7 percent and the Green Party's Jill Stein at 3 percent.
Sixty-four percent of Americans say Trump is unqualified to lead the nation. Fifty-six percent of the public say the business executive doesn't represent their beliefs
Nearly one-third of Republicans and Republican-leaning independents say Trump is unqualified for office, and 18 percent say he does not represent their beliefs.
A smaller majority overall disapprove of the way Clinton has handled questions about her use of personal email when she served as secretary of state (56 percent).
The poll was conducted June 20-23 after the massacre in Orlando by a man who pledged allegiance to the Islamic State.
President Barack Obama's approval rating was at 56 percent — his highest level in Post polling since May 2011, after the killing of Osama bin Laden.
The Post-ABC poll was conducted among a random national sample of 1,001 adults reached on cellular and land-line phones with a margin of sampling error of 3.5 percentage points.
An average of polls from June 10-23 by RealClearPolitics gives Clinton a 6.8 percentage point lead over Trump: 46.4 to 39.6
Trump, who has revoked the press credentials for the Washington Post, was critical of the Post-ABC poll, calling it a "disgrace."