Five things to watch at GOP debate
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The Republican presidential debate in Detroit on Thursday night is set to be as fierce as any, with the candidates squaring off just days before eight states and the District of Columbia cast ballots.

The debate stage will be fitted with the smallest number of candidates yet – Ben Carson’s withdrawal from the event this week has whittled the field down to the final four.

Here are five things to watch for as Ted CruzRafael (Ted) Edward CruzSenators introduce bill to overhaul sexual harassment policy Greatest risk to the Republican majority? Rising interest rates GOP Senate primary heats up in Montana MORE, Marco RubioMarco Antonio RubioAdministration works to assuage critics over ZTE deal Hillicon Valley: Judge rules Trump can't block Twitter users | ISIS content finds a home on Google Plus | Rubio rips ZTE demands as 'terrible deal' | Bill would protect kids' data Overnight Finance: Trump eyes 'different structure' for China trade deal | Trump mulls auto import tariffs | Banks get green light to offer short-term loans MORE and John Kasich pull out all the stops in an attempt to derail the Donald TrumpDonald John TrumpDems seek to chip away at Trump’s economic record Trump to sign directive to reform commercial space regulations Trump on collision course with Congress on ZTE MORE freight train.

Donald Trump versus Megyn Kelly

Round two in the bitter feud between Donald Trump and Fox News anchor Megyn Kelly has finally arrived.

Kelly infuriated Trump at the first Republican debate way back in August by pressing him on past remarks he made that were derogatory towards women.

That set off a nasty public battle between the two that peaked when Trump infamously declared that Kelly had blood coming out of her “wherever.”

Trump’s beef with Fox has since spread to a large portion of the network’s on-air talent, including Charles Krauthammer and Karl Rove.

He skipped the last Fox-sponsored Republican debate — also moderated by Kelly — just before the Iowa caucuses, as well as a forum Kelly conducted in the days before the South Carolina primary.

Now, unless something changes at the last minute,millions will get to see the two lock horns once again. 

Kelly and Trump are both known to relish confrontation, so every exchange between the two should drip with tension. Get the popcorn ready.

Which Trump will show up?

Donald Trump has two debate styles and they exist on the extremes.

There’s the take-no-prisoners Trump who showed up at the South Carolina debate, in which he savaged the audience, as well as the legacy of former President George W. Bush in a state where that was supposed to be no-no.

And then there’s the Trump who stood calmly by and observed as his rivals threw everything they had at him at the debate in Houston, Texas, late last month.

Which will we see on Thursday night?

There are rumors that Trump is all but done debating, believing that his lead over the field is large enough for him to play it safe and run out the clock.

That would indicate that the Trump who shows up will be more in line with the candidate who submitted a dialed-back victory speech after a strong Super Tuesday.

That Trump appeared to be running with an eye on the general election, as he framed himself as a level-headed unifier of a party that he’s working to expand

Of course, the tension between himself and Fox News, as well as the onslaught of insults that will be thrown at him by his desperate rivals, could be enough to light the fuse on the Trump tinderbox.

The Rubio offensive

Rubio stunned observers at the last debate who had become accustomed to his on-message style and strict policy of steering clear of Donald Trump.

In Houston, Rubio emptied the opposition research file on Trump and came packing countless television-ready takedowns. Even Trump at one point congratulated Rubio on his “nice sound-bite.”

Rubio has turned up the volume on his insults in the days since, assailing Trump on everything from his hair, to the color of his skin, to the size of his hands, and by insinuation, the size of his manhood.

But Rubio is having to answer to critics for his campaign’s negative turn, and there’s little evidence that it’s paying off. Trump won seven states on Super Tuesday compared to only one for Rubio.

Still, Republicans opposed to Trump see no other way to tear him down, and believe that humiliating him, or “unmasking the con-man,” as Rubio put it, is the best strategy.

Expect Rubio to show up armed with new insults, controversies and rumors of scandals that have touched Trump over the course of his decades in public life.

The case for Cruz

Cruz was largely an afterthought to Rubio’s nuclear offensive against Trump in the last debate, but he reestablished his presence in the race on Super Tuesday by posting three key victories.

Cruz is running second in the delegates race, feeding the argument that he’s the most credible alternative to Trump, even if the Texas Republican remains mostly reviled by the Republican establishment.

Expect Cruz to make that case for a one-on-one showdown against Trump with gusto on Thursday night. 

Cruz badly needs the field to shrink for him to have a chance at Trump over the long haul, so he’ll be looking to embarrass John Kasich, who has yet to win anywhere, and Rubio, who has only won the Minnesota caucuses, for hanging around too long.

It’s an argument that could appeal to Cruz’s critics. Even Sen. Lindsey GrahamLindsey Olin GrahamThe Hill's 12:30 Report — Sponsored by Delta Air Lines — GOP centrists in striking distance of immigration vote Dem leaders request bipartisan meeting on Russia probe Senate GOP urges Trump administration to work closely with Congress on NAFTA MORE, who has long been one of Cruz’s fiercest rivals, seems to be coming around.

"You know Ted Cruz is not my favorite, by any means,” Graham said as it became clear Cruz would be the only non-Trump candidate to emerge with much of anything on Super Tuesday. “But we may be in a position where we have to rally around Ted Cruz as the only way to stop Donald Trump, and I'm not so sure that would work.”

State politics

The Flint, Mich., water crisis has gone national, with the state’s Republican Gov. Rick Snyder — who was at one point mentioned as a potential presidential candidate this cycle — in the crosshairs.

Democrats are already seeking to make hay on the scandal, framing GOP leaders in the state as craven politicians who poisoned young children to save a few dollars.

Hillary ClintonHillary Diane Rodham ClintonMueller moves ahead with Papadopoulos sentencing What's wrong with the Democratic Party? Just look at California BBC: Ukraine paid Cohen 0K to set up talks with Trump MORE is planning to take that message to voters in the fall, and it could be a potent one in a swing-state that leans Democratic in presidential years.

While the crisis won’t get nearly the attention Thursday night as it will in Sunday’s Democratic debate in Flint, how the eventual GOP nominee responds could have implications in what’s sure to be a hotly contested general election race down the line.

It could also have an impact on how the GOP candidates fare in the Michigan primary, which will take place on Tuesday.