Clinton, meanwhile, looks set to build on her huge win in South Carolina on Saturday to sweep through southern primaries where her overwhelming advantage over Sanders among African-American voters is almost certain to be decisive.
Sanders, who is keen to challenge the growing narrative that the former secretary of state is now on track to win the nomination, hopes to halt the Clinton tide in Minnesota, Colorado and Oklahoma and will likely pocket Vermont.
A total of 595 Republican delegates are up for grabs in 11 states of the 1,237 needed to clinch the GOP nomination in 11 states. Sanders and Clinton are facing off in 11 states for 865 of the 2,383 delegates needed to win the Democratic race.
Super Tuesday is coming at a pivotal moment in the Republican race. It has finally dawned on rival campaigns and alarmed party establishment figures that Trump — after three thumping wins in New Hampshire, South Carolina and Nevada — will win the nomination unless there is a dramatic reversal of fortunes.
The former reality television star who has turned American politics upside down with his outsider campaign, nationwide media blitz and crusade against political correctness, is going into Super Tuesday with his polling hitting new peaks.
A national CNN/ORC poll published on Monday shows that Trump has lifted the ceiling on his support that for months hovered around 30% and now has the support of 49% of Republican voters, more than 30 points ahead of Rubio and Cruz.
Quality polling has been sporadic in some Super Tuesday states, but there are clear signs that Trump leads in Alabama, Arkansas, Georgia, Massachusetts, Virginia and Tennessee. Cruz appears to be clinging to a moderate lead in Texas.
Trump’s surge has some senior party figures registering alarm that his presence at the top of the Republican ticket, given his controversial rhetoric and stances on issues like immigration, could cost the party not just the White House but control of the Senate as well.
“We can’t have a nominee be an albatross around the down-ballot races,” Republican Senate Majority Whip John Cornyn told CNN Monday when asked if he had concerns about the prospect of Trump winning the GOP race. “That’s a concern of mine.”
Exacerbating the fears of the party establishment, Trump struggled Monday to extricate himself from a controversy that erupted after he initially failed to disavow the support of David Duke, a leader of the Ku Klux Klan, during a CNN interview. Trump blamed a malfunctioning earpiece for the oversight but his rivals pounced.
“I don’t care how bad the earpiece is, Ku Klux Klan comes through pretty clearly,” Rubio said during a rally in Tennessee on Monday.
Super Tuesday was once seen by the Cruz campaign as the moment when the Texas senator would build on his support among ideological and evangelical conservative voters and sweep across the South. But Trump upset his best-laid plans.
Now Cruz is left with a nervous wait to see if he will win his home state of Texas, which has the most delegates available Tuesday with 155. Failure to convert a win on home ground would effectively end his campaign.
Cruz rehearsed an argument on Monday that only he, and not Rubio has shown the capacity to win states and to take on Trump.
“I believe after Super Tuesday, we will see this race become more and more a two man race,” Cruz told reporters on Monday.
“I think the likely outcome of tomorrow – Donald is going to come out with a whole bunch of delegates. I believe we’re going to come out with a whole bunch of delegates. And I think everyone else will be way, way behind.”
Since Tuesday’s contests will award delegates proportionally based on a candidate’s share of the vote as long as they reach a certain threshold in some states, it will not be possible for Trump to clinch the nomination outright on Tuesday night.
Rubio and Ohio Gov. John Kasich are clinging to the hope that they could win their own states on March 15, when contests start to become winner take-all affairs, and eventually overhaul Trump’s delegate total.
Rubio is building a case that Trump would be a disaster for Republicans and that only he could unite the party and beat Clinton in a general election.
“I intend to be in this race as long as it takes to prevent someone like Donald Trump who is not a conservative and is a con man from taking over the conservative movement and the party of Reagan,” Rubio told Fox News on Monday. “I do not believe Donald Trump can get 1,237 delegates, which is what you need to become the nominee. And I will never give up the fight.”
Clinton’s aides know that she cannot knock out Sanders on Tuesday, but they hope to end the night with a lead of around 100 earned delegates.
Sanders is making clear that despite the size of his defeat in South Carolina — equal to nearly 50% of the vote — he is nowhere near giving up his campaign, though the candidate himself appears to have rock-bottom expectations in the South.
A Monmouth University poll of the Democratic race published Monday suggested Sanders is in good shape in at least one of those target states, showing that he leads the former secretary of state by 48% to 43% in Oklahoma.
And in Massachusetts, in his last pre-Super Tuesday rally on Monday night, the Vermont senator had an upbeat message.
“Tomorrow there will be 700 delegates up for deciding. We anticipate winning many of them and a majority of them right here in Massachusetts,” he said.
Clinton, however, appeared to be looking on toward the general election — and Donald Trump.
“You know America never stopped being great,” she said in Northern Virginia, referring to Trump’s campaign slogan. “We have to make America whole.”