Hillary Clinton has been handed a gift, but she may be the worst-suited politician in America to use it.

President Obama, who has endorsed her and for whose third term she is effectively running, is leaving the Oval Office with approval numbers no worse than even. At the same time, Clinton's Republican opponent, Donald Trump, is the most divisive and unpopular major party presidential nominee in recent history.

His unfavorable ratings are historically high, not just among voters as a whole but among Republicans too.

Given this, Democrats should feel confident as they convene in Philadelphia this week to nominate Clinton. Yet as matters stand, they must feel uneasy despite all these advantages.

If Trump were not in this race, Clinton would be the most unpopular major-party nominee in the history of presidential polling. After a 25-year record of serial dishonesty, her unfavorable ratings were already nearly as high as Trump's when the summer began.

And they've declined steadily ever since the FBI found that she carelessly mishandled classified information, even though the bureau did not recommend that she face criminal prosecution.

It's the result of clear evidence that she lied to Congress and the public. In an effort to explain away her illegal concealment of official work from the government and public, Clinton told a series of self-serving falsehoods to avoid responsibility.

After concealing her government work emails for six years, she lied about having handed them all over. She lied about why she had gone to such elaborate lengths, setting up a server in her own home, when she claimed it was so that she wouldn't have to carry multiple devices (she did so anyway).

She feigned ignorance when asked by journalists whether her server had been wiped — "with a cloth?" she asked fatuously and disingenuously. She lied when she said she hadn't sent or received classified information, and then later that at least none of it was marked classified (some of it was).

And she was deliberately misleading, as FBI director James Comey made clear, when she argued that it makes a difference whether material is marked classified.

This and other deceptions have left the impression that Clinton will say anything, no matter how easily checked and disproved, to evade responsibility for her actions. This public profile of dishonesty will loom over Philadelphia all week and will be difficult to transcend.

Two weeks ago, a Washington Post/ABC News poll found that 56 percent of adults and 31 percent of Democrats disapproved of Comey's recommendation not to indict Clinton. To put it another way, a big majority of Americans believe she should be facing a criminal trial instead of standing for election.

Likewise, 57 percent of all adults and 63 percent of self-described independents said the incident worries them about how Clinton would conduct herself as president.

In a more recent NBC/Survey Monkey poll, only 28 percent said they believe Clinton is "honest and trustworthy," with 69 percent disagreeing. This is even worse than the already-troubling numbers she posted on this question earlier.

Clinton's numbers are as bad as Donald Trump's, and thus they throw the outcome of the 2016 election into serious doubt. The candidate has earned every bit of the public skepticism and poll repudiation that she is receiving.

Before the election began, it was already assumed that she would not be able to inspire Democratic turnout at Obama-like levels. That a supermajority of Americans lacks confidence in her honesty and character only adds to the difficult task she faces.

When Democrats select Hillary Clinton as their presidential nominee this week, they will no doubt take comfort in the idea that, though not nearly as captivating as Barack Obama or even Bernie Sanders, Clinton is "likeable enough" to win the presidency. It's hardly a compelling slogan or campaign theme.

She has failed throughout her bid for the White House to say persuasively why anyone would want her there, other than that it is a woman's turn in general and her turn in particular. It's a desultory way to seek the most important job in the country. She does not deserve it — and she may not get it.