Is Super Tuesday going to be Super Trumpday?

Donald Trump’s angry army is poised to march across 11 states Tuesday with enough firepower to anoint him the inevitable Republican nominee by day’s end, while Marco Rubio and Ted Cruz are just aiming to survive the onslaught.

The biggest day of primary and caucus voting of 2016, stretching from New England to Alaska, is a make-or-break day for the real estate mogul’s rivals. It’s also a day that threatens to tear apart the Republican Party.

The challengers’ latest weapon involves tax returns. Trump Sunday again refused to release his, and would not tell “Fox News Sunday” his gross income, tax rate or charitable contributions. “I’m being singled out,” Trump complained.

Rubio, a senator from Florida, and Cruz, a senator from Texas, released partial returns Saturday for the past few years. Cruz charged on NBC’s “Meet the Press” that Trump’s returns would contain bombshells, perhaps ties to the Mafia.

Cruz once saw Tuesday as his big day, when the Christian right voters he so feverishly courts would give him victories across the South. Instead, he’s spending the campaign’s last hours fighting to avoid an embarrassing setback in his home state.

Rubio is now the clear GOP mainstream alternative, and is hoping Cruz is staggered enough Tuesday that the race becomes a one-on-one battle with Trump. Rubio’s spent the past week provoking Trump on his own playing field, unleashing insults (”he’s a clown”) and accusations (”exploiting working Americans for 40 years”) with Trump-style fury. He’s also warning a Trump win could mean doom for the Republican Party.

All this sets a gilded stage for Trump, who leads in polls in eight of the 11 states. By the time voting ends, Republicans will have awarded 595 convention delegates, or nearly half the 1,237 a candidate needs for nomination. A big Trump night means a big, maybe insurmountable, Trump lead.

“There is no doubt that, if Donald steamrolls through Super Tuesday, wins everywhere with big margins, that he may well be unstoppable,” said Cruz on CBS’ “Face the Nation” Sunday. He added hopefully, “I don’t think that will happen.”

Time is running out for his challengers. Between March 5 and 15, delegates will be awarded in primaries and caucuses in 13 more states plus Puerto Rico, the District of Columbia and the Northern Mariana Islands. And a rules change March 15 make it easier for a state’s winner to get all of its delegates.

Tuesday’s biggest prizes are Texas with 155 delegates and Georgia’s 76. Should Cruz falter in Texas, which polls say is unlikely, he’s probably finished as a candidate, though a victory would only be seen as little more than something expected. Trump has made a strong push here, appearing Friday with Gov. Chris Christie of New Jersey as his newest supporter.

Georgia once had the look of a strong Cruz state, since nearly two-thirds of its GOP voters regard themselves as evangelicals and Christian right favorite Mike Huckabee won eight years ago. Instead, polls have shown Trump with a consistent lead. Rubio is aiming to win delegates in suburban areas; Cruz is targeting smaller, more conservative communities.

Trump is ahead in other states with big Christian right electorates – Oklahoma and Alabama.

The Southern states best positioned to break Trump’s grip are Tennessee and Virginia. Gov. Bill Haslam and Sen. Lamar Alexander of Tennessee back Rubio.

In Virginia, center-right Republicans of the Washington suburbs have shown little taste for Trump, and Rubio planned to spend most of Sunday campaigning in the state. But Trump has courted both states’ religious communities; in Virginia, evangelical leaders Pat Robertson and Jerry Falwell Jr. have endorsed him.

Massachusetts, Vermont, Alaska and Massachusetts also vote Tuesday, and Rubio hopes to win at least one. Trouble is, so does Gov. John Kasich of Ohio. Kasich is betting his let’s-get-along, pragmatic style helps him in Michigan’s March 8 primary and a week later in Ohio, Illinois, Florida, Missouri and North Carolina. But getting shut out this week could drain prospects for momentum.

What’s driven voters so far is a frustration, and even vitriolic anger, towards government.

“Trump is speaking to people who feel they have not been heard,” said Melissa Nixon, a stay at home mother in Katy, Texas.

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Will they rise up again Tuesday? Can Rubio surge as the anti-Trump? Here are three key questions voters could answer Tuesday:

How can Rubio look like a winner without actually winning?

So far he hasn’t won anything. Yet his list of establishment backers keeps growing, and senior adviser Todd Harris enjoys describing “the growing anti-Trump movement in the party.” As long as Rubio keeps accumulating delegates, his campaign’s thinking goes, victories are not crucial, and his warnings about the demise of the party could be a strong motivator.

Voters are divided about Rubio’s plunge into the mud with Trump. Jane Dunlap, a small business owner in Katy, Texas, found herself “disgusted with the behavior of our candidates” during Thursday’s debate. “I don’t believe the people I was considering (Rubio and Cruz) are mature enough.”

Can Cruz surprise everyone?

Cruz plans to spend Monday barnstorming Texas, strong evidence that he’s struggling to simply stay viable. At the moment, though, Cruz is behind Trump in polls in six of the states where at least 37 percent of the voters are evangelical.

Are expectations too high for Trump?

He now has the burden of being the front-runner, the candidate everyone expects to not only win, but win big.

Trump’s forces say that’s fine with them. But he faces some new controversies. He struggles to explain any sort of comprehensive health care policy. His rivals won’t let him forget that he’s got a long history of being friendly with Democrats. He’s under fire from Mexican officials. And there’s those tax returns.

David Lightman: 202-383-6101, @lightmandavid