MILWAUKEE, Wisconsin — It’s fight night here in Milwaukee as 2016 GOP presidential candidates prepare to debate on the Fox Business Network. This fourth 2016 GOP debate comes as Obamatrade—and specifically the Trans Pacific Partnership (TPP) portion of it—moves to the center of the campaign discussion, separating the various candidates.

The frontrunner, billionaire businessman Donald Trump, is adamantly opposed to TPP and just this morning rolled out a new trade policy platform plan in which he details how he’d block China from committing further financial damage against America. Trump considers the deal “insanity.”

Dr. Ben Carson, another outsider who’s been surging underneath Trump, has just expressed openness to backing the TPP deal.

Carly Fiorina, the former CEO of Hewlett-Packard, is against the TPP deal. “There’s a whole bunch of stuff in there that can only be described as crony capitalism, special giveaways to certain industries,” Fiorina said on Breitbart News Daily this week, also adding the agreement is “a mess.”

Former Florida Gov. Jeb Bush and Ohio Gov. John Kasich both support the deal, while Sen. Marco Rubio (R-FL) now says he’s undecided after previously backing the TPP deal multiple times. As a Senator, Rubio also provided the critical 60th vote for Obamatrade’s Trade Promotion Authority (TPA)—something that greases the skids for TPP, making it extraordinarily more difficult for Congress to block the pact.

Sens. Rand Paul (R-KY) and Ted Cruz (R-TX)—who both voted against the final TPA, after Cruz initially backed TPA—are likely opposed to TPP, but haven’t formally announced positions on the deal.

With his trade deal, however, President Barack Obama is yet again driving the conversation in the GOP primary.

Another question heading into this fourth GOP debate is whether the moderators will be better than their rivals in prior debates.

Fox News’ Megyn Kelly came under criticism, as did fellow moderators Chris Wallace and Bret Baier, for how they handled the first debate in Cleveland, in August.

Then Jake Tapper came under scrutiny for not letting Hugh Hewitt ask more questions in the second debate, hosted in September by CNN in Simi Valley, California.

CNBC’s John Harwood, Becky Quick and Carlos Quintanilla came under huge criticism for their debate in late October just over a week ago in Boulder, Colorado.

All eyes this evening will be on Fox Business Network’s Maria Bartiromo and Neil Cavuto and the Wall Street Journal’s Gerard Baker. It’s unclear how they will do, but it has been reported Fox Business wants to outshine CNBC.

After tonight, there are only two more debates before the first votes are cast in the Iowa Caucuses, on Monday Feb. 1.

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