The Republican Party is petrified.  Not because the leading presidential candidate Donald Trump has declared war on it.  Nor is it because he is not a real conservative.  And it's not even because of his rash statements that many in the Party see as racist, xenophobic, misogynistic or just plain nuts (like arming South Korea and Japan with nuclear weapons so they could better defend themselves).The GOP is petrified that the 2016 presidential election it thought was theirs for the taking, shows a clear path to defeat.Both of the current leading candidates, Donald Trump and Ted Cruz, are detested by the GOP establishment.  Republican Sen. Lindsey Graham described the prospect of having to choose between the two as having to choose between "being shot or poisoned". In fact Cruz is so disliked by his Senate colleagues, Graham suggested that "If you kill Ted Cruz on the floor of the Senate, and the trial was in the Senate, nobody could convict you".  Cruz endorsements from fellow Republicans are often excruciating to watch.While Trump's candidacy has drawn hundreds of thousands of new voters to Republican primary elections and he has a healthy lead among Republican voters nationally ( 43% for Trump, 31% for Cruz, and 19% for John Kasich), many in the general voting population that includes Democrats and Independents, have an unfavorable opinion of him.  In this broad voter group about 2 out of every 3 disapprove of Trump.  Among women disapproval rises to 70%.  This degree of unfavorable rating for a nominated candidate is the highest ever recorded by Gallup since it started tracking this measure in 1992.While Cruz has lower negatives (50% unfavorable/29% favorable),  hence making him a more palatable GOP candidate in a general election, he significantly lags Trump on the delegate count, the number of states won, and the total popular vote in the primaries.  The likelihood of him winning even in a contested convention is slim.But lower negatives have their advantages.  A recent McClatchy-Marist poll shows that in a head-to-head contest with Hillary Clinton, voters are evenly split between Cruz and Clinton.  However, in a similar head-to-head contest with Clinton, Donald Trump loses badly (50% to 41%).A deeper analysis of the polling data reveals that for both Trump and Clinton, roughly half their supporters were voting for the candidate and the other half were voting to make sure that their opponent wasn't elected.  It seems the 2016 Presidential race is shaping up as an election of the least unlikable candidate.To make things even more confusing, the poll shows that Bernie Sanders, who is unlikely to overcome Clinton's massive delegate lead, tops Trump handily – 57% to 37%. Similar lopsided results were reported in a Sanders/Cruz matchup.  It seems American voters like Bernie Sanders a lot more than the Democratic primary delegates.In short, while the GOP primaries show Donald Trump to be a strong candidate among Republican voters, the polls show nationally he is the weakest of the three.It is precisely this conundrum that has fueled the desperate activity among establishment Republicans for a contested convention.  The math however suggests there is faint hope that this action will succeed.It seems inconceivable that Trump, with by far the largest plurality, will be unseated by Cruz (or possibly even Kasich who has only won one state, his own).  How will the Republican establishment explain this chicanery to its base, let alone the nation?Once Trump is nominated and the Republican establishment faces up to this reality, both will be forced to work together for the one thing they agree on — winning the Presidency.In order to win, Trump needs to expand his support beyond white, mostly male voters.  The four groups he has managed to alienate include women, Hispanics, African-Americans, and Muslims.He will attempt to do that by massively changing his narrative after being nominated.  This pivot is not much different from what Mitt Romney did in the “Etch-A-Sketch” reset during the last presidential election cycle after winning the GOP nomination.  The reset is unavoidable due to the inflated influence of right-wing extremism, both religious and ideological, on candidate positions in the GOP primary process.Here is how this will play out.First, Trump will totally walk back (as to some degree he has) the nonsense he spouted to MSNBC's Chris Mathews about penalizing women for having abortions.  It was quite apparent in the interview that he really had not thought through the issue.  And it is certain he will remind women that he loves them and will take care of them better than anybody. As mentioned, 70% of women presently do not approve of him. Constituting half of all voters, Trump can't ignore their displeasure and hope to win the Presidency.Secondly, he'll put forth face-saving solutions to resolve the issue of illegal Mexican immigrants.  He will admit that many of the jobs Mexicans take are too strenuous and pay too little to interest Americans.  The compromise will ensure that employers will have to take on more responsibility and provide justification for hiring low-cost Mexican labor.  And oh yes, the wall will be built -- with American taxpayer money.As former rival, now supporter Ben Carson duly noted, Donald Trump is an intelligent man when he's not talking on television.  Assuming this is true, no candidate in their right mind would propose a plan to start deporting 11 million Mexicans on his or her first day in office.  The Boston Globe has mercifully provided us with a preview of such a bonehead action.When all is said & done, Hispanic voters may not be as polarized against him as they are today and a fair number may actually vote for him.  Presently, Trump's level of unfavoribility with Hispanics stands at 77%.  Hispanic voters represent about 12% of the voting population.Thirdly, Trump will make an effort to attract more African-American voters.  He will of course have Carson by his side.  His efforts will not be too fruitful as most African-Americans seem to be strongly in Hillary Clinton's camp. Clinton's unfavorability among African Americans is 12%; Trump's unfavorability is 68%. African-Americans represent about 12% of the voting population.Lastly, Trump will continue to play the terrorist fear card as it relates to Muslims.  He knows Muslim Americans represent less than 2% of all voters.  Since 9/11, fear of terrorist attacks has been a constant feature of American life.  Polls show that year after year, a majority of Americans feel there will be a terrorist attack on American soil in the next few weeks or months.  While the reality is starkly different, the fear is there. Exploiting  these fears plays not only to his base, but voters of all political stripes.  He has more to gain by exploiting Muslims than engaging them.At the same time, Trump will continue hammering home the message that as a successful businessman, he will make deals that will bring back the good paying jobs that bad trade deals stole from America.  That won't be easy as Hillary Clinton will zero in on the fact that if it wasn't for Chapter 11 bankruptcy protection, he would have gone bankrupt several times.  For investors and employees Trump was a disaster.Trump's ace virtue, however, is that he is self-funded and is not in the pocket of Wall Street, Washington lobbyists and special interest groups.  It's what initially attracted his followers, what willmost likely win him the GOP nomination, and what ultimately could win him the presidency.It's also one virtue that Hillary Clinton cannot match as her arch-rival Bernie Sanders keeps reminding us.  More importantly, it's not at all certain that once she becomes the Democratic standard bearer, Bernie Sanders supporters will gravitate to her. About one in four indicate they would not support her candidacy.  Would they simply not vote?  Or would they hold their nose and vote for Trump?  That is the critical question.Equally critical is the question of how many Republican voters who disapprove of Trump would (also holding their noses) end up voting for Hillary Clinton.Is Trump up to the reset challenge?Well, he's “flexible”.  For all his extreme and often outrageous comments, he's not averse to retreating (although never admitting to it). And love him or hate him, he's a great communicator (sort of like Ronald Reagan, but different).  The public, as CNN, Fox, and CNBC will testify, simply cannot get enough of him.  Rightly or wrongly, many Americans trust him as much as they don't trust Washington politicians.If in the post-nomination reset Trump succeeds even partially in re-engaging with women and Hispanics, there is a good likelihood he can become the next President.All these cross currents make predicting the winner of the US presidential race in 2016 extremely difficult, but they assure us of the most exciting election in decades.Oleh Iwanyshyn has been involved in public opinion polling since the mid-70s, first with the Institute for Behavioral Research at York U niversity, then the Canadian Broadcasting Corporation and more recently with ViewStats Research, a company he cofounded in 1997.  He writes on the role of public opinion polls in matters of politics and public policy.  His articles have appeared in iPolitics, The Hill Times, and National NewsWatch. For more, see his blog poll stuff.