With Hillary Clinton and Donald Trump preparing to face off in the general election this fall, voters face a choice between two candidates with record high unfavorable ratings who are weighed down by problems that are often of their own making.
Following Clinton's victories in four of six contests Tuesday, she has the support of enough pledged delegates and superdelegates to secure the Democratic presidential nomination. Trump became the presumptive Republican nominee when his final opponents suspended their campaigns last month.
The two candidates fired opening shots in the general election race with speeches on Tuesday night, Clinton hitting Trump for being reckless and rude and Trump accusing Clinton of corruption.
From Clinton's email practices as secretary of state to Trump's many comments that have offended various segments of the electorate, the greatest vulnerabilities of both are the result of unforced errors and poor decisions.
For all of the obvious differences between Trump and Clinton, there are also similarities in their areas of weakness and their ability to overcome them.
Trump and Clinton have both lived in the public spotlight for decades, and nearly every word they have said on the campaign trail over the last year has been recorded, giving their opponents a staggeringly long list of mistakes and controversies to attack them over.
Trump has already signaled a willingness to dig up the scandals of the 1990s when Bill Clinton was president.
"If you recall the Clinton years, it was just one thing after another," said Gary Nordlinger, president of Nordlinger Associates and adjunct professor at George Washington University's Graduate School of Political Management.
Trump's background as a New York tabloid fixture and his many, many media appearances also provide fertile ground for criticism, but his comments since announcing his candidacy last June are already in Clinton's crosshairs.
Clinton's allies have unleashed ads featuring Trump saying offensive things about minorities, women, and a disabled journalist.
Her campaign quickly posted a video earlier this week highlighting the many Republicans who disavowed Trump's comments about the judge in one of the Trump University lawsuits.
In a widely viewed speech last week, Clinton picked apart numerous statements Trump has made on policy issues, using his own words against him. That strategy is likely to continue.
Voters do not trust either of these candidates.
"They both have ethical clouds hanging over their heads," Nordlinger said. While Clinton has been mired in political scandals for years, Trump has his own problems like the allegations that his Trump University venture was a scam.
Clinton has expressed regret that voters do not trust her, but it is not clear that she can do much about it.
"This honesty thing has been with her for literally decades," said Kerwin Swint, professor of political science at Kennesaw State University and author of "Mudslingers: The 25 Dirtiest Political Campaigns of All Time."
"Her strategy for dealing with that has been deny, deny, deny and distract, distract, distract," he said. He expects she will continue with that approach since it has gotten her this far.
"I think [Trump] will try very hard to focus voters' attention on her untrustworthiness," said Glenn Altschuler, Litwin Professor of American Studies at Cornell University, "and therefore he'll continue to emphasize the email controversy."
Clinton, meanwhile, is sure to highlight Politifact "Lie of the Year" winner Trump's many contradictions and lies. That did not work for his opponents in the primaries, but a general election audience might find it more alarming.
Trump's recent comments alleging that Judge Gonzalo Curiel cannot be fair to him in a Trump University lawsuit because he is of Mexican descent are the latest example of him lashing out at every perceived slight or offense.
"It has at, a critical moment in this process when candidates are defined in the minds of the electorate," Altschuler said, "defined Mr. Trump as someone who may indeed be unfit for the presidency, erratic, unable to understand the separation of powers, and in all likelihood a racist."
If vulnerable Republicans from battleground states like Ohio and Pennsylvania distance themselves from him over his statements, that will indicate significant trouble.
Since being unconventional and politically incorrect has been one of Trump's selling points, any attempt to moderate his tone is a "calculated risk," Swint said. He needs to find a balance between being seen as refreshingly blunt and just being offensive.
Trump's teleprompter-reading speech Tuesday night may be a step in that direction, but it is too soon to tell if it will stick.
"I think there's a lot of evidence that he resists that and doesn't want to surrender to that," Swint said.
"He has a tendency to double down on his comments," Altschuler said, "and since that seemed to work for him in the primaries, he is applying that strategy in the general election. But the primaries ain't the general election."
Trump responded to Clinton's criticism of his temperament last week by arguing her temperament is too soft and weak to be president. He has also latched on to an upcoming book by a former Secret Service officer who claims Clinton was erratic and violent when she was First Lady.
A recurring theme in Donald Trump's speech Tuesday night, and one that is sure to be featured in his anti-Clinton speech next week, is that she has shown consistently poor judgment.
In using a private email server as secretary of state, giving paid speeches, and accepting questionable donations through the Clinton Foundation, Clinton has created many of her own biggest problems.
Trump's critique extends to foreign policy, though. He attacked Clinton for supporting military action in Iraq and Libya, although he also supported them in the past, and accuses her of not doing enough to prevent the rise of ISIS.
"Her judgment is her strongest selling point," Nordlinger said, so if Trump is able to undermine that, it may be the path to victory.
"I think she's very vulnerable to attacks on her judgment," Swint said. Many of the examples her opponents cite are part of her long record as a public official that she has built her campaign on.
"He's not a clean vessel himself," he added, "so it's going to be hard for some voters to take that from Trump."
Clinton and others have also questioned Trump's judgment, in both foreign policy and his campaign style.
Republicans who criticize Trump have argued he cannot be trusted with nuclear weapons.
Trump's decision to introduce Judge Curiel's Mexican heritage into the campaign debate has caused potentially irreparable damage. He attempted to walk it back Tuesday by claiming his repeated claims that the judge has a conflict of interest because "he's a Mexican" were misconstrued.
Nordlinger said Trump needs to be more cautious about what he says.
"He cannot continue to say these outrageous things and, when they blow up in his face, say he was taken out of context."
"Hillary Clinton is in many ways a traditional candidate," Altschuler said. "She has considerable experience, she is a disciplined person, she's very knowledgeable about the issues, she is adept at debates."
She needs to become stronger on the stump and find a way to connect with voters, he added.
While typically an asset, her decades of political experience could be her downfall this year.
"There's an anti-establishment wave in this election," Altschuler said. "We've seen it in the response to Trump, we've seen it in the response to Bernie Sanders. Trying to leverage that is the only way for Trump to succeed."
Nordlinger also noted that Clinton is swimming against the tide of the electorate this year.
"The biggest different between Clinton and Trump is that Clinton is the queen of the political insiders and Trump is the king of the political outsiders and that is a huge Trump advantage," he said.
Trump's lack of political experience, his lack of a track record on conservative issues, and his unfamiliarity with the political system have been consistent concerns among voters who do want a more establishment candidate, though.
Although Clinton has consistently had the support of a majority of Democratic voters over Bernie Sanders during the primaries, that rarely translated to the kind of excitement Sanders and Trump have generated on the campaign trail.
If Clinton eventually receives a strong endorsement from Sanders, that could help her overcome the enthusiasm gap. Building a winning coalition could prove to be a challenge, though.
"She's not a particularly charismatic candidate, she's not a very inspiring candidate," Swint said.
With Trump and Libertarian candidate Gary Johnson also vying for Sanders voters, the Democratic Party may be harder to unite under Clinton than it was in past election cycles.
"She needs to figure out a way to reach out to Bernie Sanders' supporters, especially young people, without appearing to be craven," Altschuler said.
Trump faces different but potentially also serious enthusiasm problems. While his supporters have been the most devoted and enthusiastic in the primaries, he also faces the most passionate opposition and he must overcome a serious lack of excitement from establishment Republicans.
Polls show fear of a Trump presidency is likely to drive Democrats to the polls in November as much as, if not more than, support for Clinton does.
Given all of their apparent weaknesses and vulnerabilities, Nordlinger said, Clinton and Trump are both lucky that they may be facing the only opponent they can beat.
"It's really going to be who's successful at seeming to be the lesser of two evils."