Georgia: The Republican Party is torn between those in its ranks who would make their peace with Donald Trump and those determined to block what amounts to his hostile takeover of the party.
Why is Super Tuesday so 'super'?
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Why is Super Tuesday so 'super'?
The 1st of March 2016 is a day in the US presidential electoral cycle that fully deserves its superlative; here's why.
On the eve of Super Tuesday, when Trump is expected to win primaries or caucuses in 10 states, top Republicans held an emergency conference call to discuss the mogul's rise.
During the call, Kentucky Governor Matt Bevin asked New Jersey Governor Chris Christie to explain his shock endorsement of Trump.
Meanwhile, Republican Senator Ben Sasse has published an open letter to constituents explaining why he will never be able to support Trump.
"I sincerely hope we select one of the other GOP candidates, but if Donald Trump ends up as the GOP nominee, conservatives will need to find a third option," he wrote.
The fear and loathing gripping the party in the face of Trump's rise is being reflected in the increasingly ugly tone of the campaign.
Over the weekend Marco Rubio, who is desperately trying to position himself as the viable alternative to Trump, adopted Trump's own campaign tactic of hurling insults.
Trump, he said, had small hands and a bad spray tan.
"Donald Trump isn't gonna make America great, he's gonna make America orange," said Rubio.
By Monday, though, Rubio seemed determined to reclaim the high ground.
"Name me a single great leader in human history that is saying the things, doing the things or acting the way he's acting now," Rubio said during a rally in Atlanta, Georgia, on Monday afternoon.
"This is not who we can turn over this country to, or our party. So I ask you: go out there and let your friends know that tomorrow's an important day."
By then Trump himself was the focus of what appeared to be yet another manufactured racism controversy.
During a CNN interview on Sunday he had refused to reject the endorsement of David Duke, the former grand wizard of the Ku Klux Klan.
"I don't know anything about what you're even talking about with white supremacy or white supremacists," he said. "So I don't know. I don't know - did he endorse me, or what's going on? Because I know nothing about David Duke; I know nothing about white supremacists."
But on Monday Trump said he misheard the question regarding Duke due to a faulty earpiece.
More than once during the campaign Trump has dominated news cycles by making controversial statements only to seek to refute them the following day.
But inflaming racial tension has been a constant element of Trump's political persona ever since he first introduced himself to Republican voters by championing so-called "birther" conspiracy theories about Barack Obama during the President's first term.
Even as the KKK controversy played out, Trump maintained his aggressive posture during campaign events on Monday.
When his supporters began jeering at a protester during a campaign event in Virginia on Monday, Trump heckled her from the stage, asking "Are you from Mexico? Are you from Mexico?" as the audience laughed and chanted "USA! USA!".
The tone at his rallies has long been ugly to those who dare question him, be they protesters or media. Last week he lamented that he could not punch a protester in the face.
"You know what they used to do to a guy like that in a place like this?" Trump said. "They'd be carried out on a stretcher, folks."
The controversy has done nothing to dampen to his popularity among Republican voters who seem intent on punishing the party's establishment.
He is expected to win in at least 10 states on Tuesday, with senator Ted Cruz likely to hold on in his home state of Texas. Such a rout would nonetheless cripple Cruz, who had been depending on support in the southern states that Trump is expected to win.
It is also not clear that Rubio can win any of Tuesday's contests, making his claim to be the natural alternative to Trump hard to defend.
Hillary Clinton is expected to cement her lead over senator Bernie Sanders on Tuesday for the Democrats, with polls suggesting she will win most contests, though Sanders is expected to trounce her in his home state of Vermont.
If Sanders cannot beat her in the races outside her southern stronghold - including Colorado, Minnesota and Massachusetts - pressure is likely to begin to mount on him to quit the race.