Tuesday night's Republican presidential debate could not come at a much better time for Ted Cruz. Texas' Canadian-born junior senator is in the ascendancy. He's currently seeing his best poll numbers of the campaign, he's scoring points in rhetorical fights with the most visible candidate in the field and he continues to stack up endorsements from key figures in early primary states. Given the confidence and self-assurance he's shown in each of the previous GOP debates, it's easy to imagine Cruz coming out of Tuesday with more momentum than any other candidate on stage.

Cruz's stepping out on Trump was the clearest sign yet that he's getting progressively more confident about his place near the front of the 2016 GOP field. It's like Dan Rather said during his August visit to the Observer offices:

"Ted Cruz is like a desperado waiting on a train, in this case a train wreck," he said. "He hasn't said anything critical about Trump. When Trump is out of the race, however that goes, Cruz wants to inherit, and he's positioned himself to inherit with what the pool players call shape. Ted Cruz is playing shape and he's put himself in position [to pull in Trump's supporters]."

Polling over the weekend from Bloomberg and the Des Moines Register shows Cruz easily overtaking Donald Trump as the first choice among voters expected to attend the Iowa Republican Caucuses, scoring 31 percent of the expected vote to Trump's 21 percent. Cruz has tripled his support in about six weeks in the same poll, buoyed by endorsements from Hawkeye State social-conservative kingmaker Bob Vander Plaats and Iowa Congressman Steve King.

It's starting to appear that he might actually win — there's very little campaigning time left before the holiday lull that seeps into mid-January — and that's enough to have shattered the truce Cruz had built with Trump.

Late last week, a recording emerged from a closed-door, New York City fundraiser for Cruz. The senator can be heard saying generally nice things about Trump, before questioning whether the real estate billionaire has the judgement to be president. Trump, as he's done every time he's felt slighted throughout the campaign, struck back quickly, calling Cruz a "little bit of a maniac," referring to the way Cruz has imposed himself on the rest on congress. Cruz responded by linking to exactly the video one would expect, the famous scene from the movie Flashdance, on Twitter.

After Trump revealed his xenophobic plan to ban Muslims from coming to the United States for any reason, the Cruz campaign smelled blood in the water and finally went after him. The campaign is doing the same thing to Marco Rubio, the guy widely consider to be the biggest threat to Cruz's eventual nomination should Trump collapse. 

In a new ad, Cruz surrogate Congressman Jim Bridenstine goes after Rubio for being part of the "Gang of Eight" senators who worked on Congress' most recent attempt at comprehensive immigration reform. Rubio is lambasted for the conservative apostasy of supporting "amnesty" for undocumented immigrants. Bridenstine throws an additional punch by suggesting that the Gang of Eight deal would've allowed the increased admission of refugees to the country. Like the Syrian ones everyone is up in arms about.

Ahead of the debate, there are also signs that Cruz might be about to pick up a key national endorsement as well. Late yesterday, Cruz tweeted to ask his supporters to help retire the campaign debt of erstwhile GOP candidate Scott Walker, the Wisconsin governor who couldn't get his campaign off the ground despite extensive backing from the Koch brothers.

After Iowa, Cruz will face a much tougher test in New Hampshire — the Granite state's more secular electorate has been less friendly to Cruz's religious conservative message. Just around the corner after that primary, though, is the so-called SEC primary on March 1, highlighted by its biggest prize, Texas.

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