Carly Fiorina may well be the Republican candidate to watch during Wednesday’s second GOP presidential debate – if you’re looking for a break-out performance by a third tier candidate who has staked her claim to relevance based largely on her role as the ”anti-Clinton” – an articulate and forceful speaker who can turn the Democratic party’s traditional gender advantage on its head. Her ongoing kerfuffle with Donald Trump has allowed her to claim the national media spotlight – and she’s clearly making the most of it.

But the main man to watch on Wednesday is not Trump or even Jeb Bush, let alone Scott Walker, whose once-promising candidacy has virtually collapsed in recent weeks. It is Ben Carson, whose extraordinary surge in the polls has left many mainstream media pundits – Democratic and Republican-leaning alike — dumbfounded. In the space of a month, Carson has moved from the conservative fringe to the center of the presidential race. He’s not only solidly in second place in the national polling among GOP candidates, he is also polling extremely competitively against Hillary Clinton. In fact, in the latest CNN/ORC poll, released last week, he’s leading the former Secretary of State by five points, 51-46 percent, the largest advantage over Clinton that any GOP candidate has claimed to date.

Let’s look closer at the CNN poll to see why Carson is leading by such a strong margin. It’s probably no surprise that Carson is polling strong among Tea Party supporters and among Republicans general – as a strong as Trump is and stronger than Bush. However, Bush is barely beating Clinton among self-described independents (50-45 percent) and is losing badly among self-described moderates (56-41 percent). Trump fares even worse: A slight lead among independents (49-45 percent) but he is trounced by 21 points among self-described moderates 58-37 percent. But compare these numbers to Carson’s. He’s soundly beating Clinton among independents (by 14 points, 55-41 percent) but also trailing by just five points among moderates, (52-47 percent).

Next, consider age and education. Bush and Clinton poll nearly evenly among college attendees. Bush leads slightly among those under 50, while those under 50 tilt Clinton. That’s to be expected. Not surprisingly, perhaps, for Trump these disparities are wider: He trails Clinton by 9 points among under-50 voters and by 7 points among those with college education.   

But here again Carson breaks the mold. He leads Clinton by 5 points among those under 50, and by 6 points among those over 50. He also has an 8-point lead over Clinton among those with college education. The upshot? As with political orientation, Carson displays a substantially broader voter appeal than either Bush or Trump.

In fact, Carson’s appeal is not just broader: it’s a stronger appeal to constituencies that are more likely to vote Democratic – younger, more educated voters. This is even more obvious when we look at how Bush, Trump, and Carson match up with Clinton when it comes to “non-White” voters. President Obama captured 89 percent of this entire block, which includes Latinos, African-Americans and Asians, during his re-election bid in 2012. Mitt Romney obtained a paltry 11 percent. According to CNN, Bush and Trump are likely to get 26-28 percent, a huge jump which would likely make either candidate far more competitive than Romney was in key states like Latino-rich Florida and Nevada or states like North Carolina and even Ohio, where African Americans are influential. For Republicans, that’s clearly good news.

But here again, neither Bush nor Trump can compete with Carson, who captures a whopping 38 percent of the “non-White” vote (10-12 points higher), compared to just 58 percent for Clinton. It is unclear from the CNN poll how much of this difference might be due to a high African-American affinity for Carson, as opposed to a higher Latino or Asian support. It’s a reasonable assumption that Carson might be benefitting from co-ethnic support from Blacks. Whatever the source – it’s a powerful finding and further illustrates what appears to be Carson’s unique cross-over appeal.

A fluke, you say? Perhaps, but CNN’s poll is not the first to show Carson running competitively against Clinton, on par with other GOP candidates. Three weeks ago, Public Policy Polling found a similar result. And consider this, too.  When Joe Biden is added to the mix, Trump and Bush completely lose their polling advantage. Biden leads Trump by 10 and Bush by 8. But not Carson. He still leads Biden by three, just two points less than his 5-point lead over Clinton. All told, Carson does 10-13 points better against Biden than either Bush or Trump. Which means Biden’s hypothetical advantage over Clinton as the Democratic candidate might well disappear if Carson is the GOP nominee.

None of these extraordinary results mean that Carson will get a chance to test his distinct head-to-head polling advantage in the actual field of battle. Trump is still leading Carson and the rest of the GOP field in the race for the Republican nomination by a large margin. But stay tuned on Wednesday. The Trump-Fiorina stand-off, if there is one, and the response of the other GOP candidates, could mark something of a turning point in the race, especially if Republican women begin to sour on Trump. And it just may be that Carson, who some already consider a kinder, gentler, and more thoughtful version of Trump, ends up the big winner.