“You’re likable enough, Hillary.”  

It’s one of the most famous political put-downs, then-Sen. Barack Obama’s stinging primary debate rejoinder to Hillary Clinton on Jan. 5, 2008. And even though it may have been Obama’s least likable moment of the campaign — and he went on to lose the New Hampshire primary to Clinton a few days later — the micro-aggression suggests a question that every presidential campaign faces: Just how likable to do you have to be to get invited into America’s livings rooms (and onto its iPads and smartphones) for the next four years?  

If likability is as essential as we’ve always assumed, for that office as for no other, then the 2016 presidential campaign is going to be very interesting, because the front-runners in both parties by and large have negative images, according to recent opinion surveys. And many of them have the added baggage of either being well-known quantities, like Clinton or Donald Trump, or being associated with a deeply unpopular Congress, like Sens. Ted Cruz, R-Texas, and Marco Rubio, R-Fla.  

Cruz  is surging in Iowa’s first-in-the-nation caucuses, with Republicans in the Hawkeye State pushing him to the front of the pack ahead of Trump, Ben Carson and Rubio.  

But in the latest YouGov/Economist public opinion survey, conducted Dec. 4-9, Cruz has an unfavorable rating of 41 percent among the 2000 adults surveyed. That outpaces his favorable ratings, which stood at 34 percent. Twenty-five percent were undecided, suggesting there is room for growth.  

Cruz has gone out of his way to say he didn’t come to Washington to make friends, and his relationships with his Senate colleagues indicate he’s made good on that promise. In one of the best pot-meets-kettle moments so far in this campaign, Trump even went after Cruz for his lack of tact over the weekend, saying on this past weekend’s “Fox News Sunday,” “You can’t walk into the Senate and scream and call people liars and not be able to cajole and get along with people. He’ll never get anything done.”  

In September, Cruz failed to get a second senator to sign off on his push to add language defunding Planned Parenthood to a continuing resolution to fund the government. Sen. John McCain, R-Ariz., told Roll Call’s David Hawkings he’d never witnessed such a thing: “I’ve never before seen a senator who couldn’t get even one other person in the Senate to raise his hand to help him get a vote.”  

Last December, during another showdown over government funding, Cruz delayed a vote on year-end spending, which angered his colleagues who were forced into a weekend session and enabled Democrats, in the last gasp of their majority, to approve a number of Obama’s nominees they otherwise would not have been able to accomplish.  

Not one of Cruz’s fellow senators has endorsed his presidential race , though 12 House members have come out for Cruz.  

Rubio, who is not as combative toward his presidential rivals or Senate colleagues, has a more balanced favorable/unfavorable rating, according to the YouGov/Economist survey. Rubio has a 38 percent favorable rating and a 36 percent unfavorable rating, within the survey’s 3-point error margin.  

Of Rubio’s 21 congressional endorsements, three of his Senate colleagues, Jim Risch of Idaho, Steve Daines of Montana and Cory Gardner of Colorado, have endorsed his candidacy.  

Trump, known for extreme statements such as calling for a ban on Muslim immigration and also for personal insults such as calling Cruz a “maniac” over the weekend, has a 55 percent unfavorable rating and a 39 percent favorable rating. Carson is the only one of the four in the top tier who had a clearly more favorable rating, with a 45 favorable and 36 percent unfavorable rating.  

On the Democratic side, Clinton has an even higher unfavorable rating than Cruz or Rubio, at 50 percent, in the latest YouGov/Economist survey. Her favorable rating was 44 percent. The 5 percent who said they were undecided is not surprising, considering how long she has been in the public spotlight, from her time as first lady (1993-2001) to a senator from New York (2001-2009), secretary of State (2009-2013) and now full-time candidate.  

She evokes strong reactions among partisans, and has a whopping 164 congressional endorsements.  

Among Republicans, 77 percent had a very unfavorable opinion of Clinton, while only 49 percent of Democrats had a very favorable opinion. Thirty-eight percent of independents said they had a very unfavorable opinion, and 14 percent said a very favorable.  

Sen. Bernard Sanders, the independent from Vermont who is challenging Clinton for the Democratic nod, had a 44 percent favorable rating and a 35 percent unfavorable rating. He has no endorsements from his Senate colleagues and two endorsements from House members.  

Cruz, Rubio and Sanders also have the disadvantage of serving in an unpopular institution. According to the Gallup organization’s most recent poll tracking, the legislative branch had only an 11 percent approval rating, facing off a whopping 86 percent disapproval mark. The 11 percent figure was the lowest in at least two years.  

Perhaps it’s no wonder Cruz describes the Washington establishment, including his own congressional leadership, as a “cartel.” Rubio, meanwhile, has the lowest attendance rate for Senate roll call votes. He may feel there would be little to gain in showing up to work for his current employer.