The conventional wisdom among Donald Trump’s detractors is that his current surge in the polls won’t last because as we get closer to actual voting, Republicans excited by his political incorrectness will start factoring in “electability.” When GOP voters realize that he can’t beat Hillary Clinton, the theory goes, they will switch their support to other more electable candidates.

One problem with that theory: Right now, GOP voters believe Trump is the most electable candidate.

A new Post/ABC News poll asked GOP-leaning voters which candidate “has the best chance of getting elected president in November 2016?” The winner was Trump by a landslide. An incredible 43 percent of GOP voters say that Trump is the most electable GOP candidate. In a distant second place, Ben Carson trails Trump on electability by 27 points, while Jeb Bush — whose entire rationale for his campaign is electability — trails Trump on electability by 30 points. Since the same poll found Trump with 32 percent support, that means even GOP voters who do not support Trump still believe he is most likely to beat the Democrats in 2016. A new Associated Press-GfK poll confirms this, finding that “Seven in 10 Republicans and Republican-leaning registered voters say they think Trump could win in November 2016 if he were nominated; that’s the most of any Republican candidate.”

This perception of Trump’s electability perplexes the GOP establishment, which is certain he would lose to Hillary Clinton. But Trump has closed a 24-point gap in June with the presumed Democratic nominee (though the Real Clear Politics average still shows Clinton leading Trump by 2.5 points). Trump’s protectionist trade message and his attacks on China and Mexico resonate with Reagan Democrats in states such as Ohio and could give him crossover appeal in a general election. Whether he can actually win is an open question, but so long as GOP voters believe he can win, then “electability” is not going to be the pin that pops the Trump balloon.

Republicans also see Trump as the only candidate who can truly shake up Washington. In a CNN/ORC swing-state poll, 60 percent of Republican primary voters in Nevada say that Trump is “most likely to change the way things work in Washington” while in South Carolina he is seen as the best agent of change by 58 percent. No one else in the GOP field even approaches those numbers — except for Carson, the rest are in single digits.

At a rally in Jacksonville, Fla. on Saturday, Oct. 24, Republican presidential candidate Donald Trump says both Jeb Bush and Ben Carson have low energy. (Reuters)

So right now Republican voters believe that Trump is (a) the most likely to shake up our nation’s capital and (b) has the best shot of winning in November.

What could cause that perception of Trump’s electability to change? The most likely way would be for him to have a really bad debate performance. But Trump has an unlikely protector: the GOP establishment. After Mitt Romney’s 2012 battering, Republican leaders decided to limit the number of debates in order to protect the next front-runner from excessive debate scrutiny. Their plan is working perfectly — except the beneficiary is Trump.

Consider: In 2012, Republicans had already held eight debates by this time in the election cycle. This time, there have been just two. After Wednesday’s debate hosted by CNBC, there will be just three more before the first ballots are cast in Iowa.

Moreover, Trump succeeded in forcing CNBC to cut the length of its upcoming debate from three hours to two and to allow candidates to burn some of that limited time with opening and closing statements. That will reduce the danger that Trump will have to engage other candidates in substantive discussions, or suffer a moment where he looks out of his depth that could undermine GOP voters’ confidence in his electability. In the Fox News debate, with similar rules, Trump spoke for a total of 11 minutes and 14 seconds. At that pace, he will have just 45 minutes of speaking time on the debate stage between now and the time the first votes are cast.

That’s just how he wants it. And who can blame him? As the front-runner, Trump has nothing to gain and everything to lose from more debate time.

He’s right to be careful, because the GOP electorate is still volatile. In South Carolina, for example, only 19 percent of Republicans say they have “definitely decided” which candidate they are supporting, while 60 percent say they are “still trying to decide.” And two new polls last week show Trump trailing Carson in Iowa by 8 and 9 points respectively — the first time he has not been in the lead there since June.

So Trump — master of the “art of the deal” — has not closed the deal just yet. To stop him, the GOP field will have to winnow considerably. And for one of the remaining Republicans to win, he or she has to convince GOP voters first that Trump can’t win, and second, that he or she is a credible alternative to shake up Washington.

That’s a lot to accomplish in 45 minutes.

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