It often seems the world's craziest political race can't get any crazier. But it constantly does.

I've been following it for its potential to kill the Trans-Pacific Partnership (TPP) trade agreement, where there's a new threw-the-looking-glass twist, as reported by the Wall Street Journal:

Some Republicans think Mr. Trump’s opposition to the Trans-Pacific Partnership, a 12-nation trade pact, might actually help boost its congressional support. “We might get a lot more Democrats on board under that circumstance,” mused Senate Finance Committee Chairman Orrin Hatch (R., Utah).

Senator Hatch's comments come at a time when it's looking more and more likely that Donald Trump has the Republican nomination wrapped up.

The received wisdom was that "Super Tuesday" (when a dozen southern states hold primaries on the same day, March 1) would act as a firewall to stop the crass New Yorker's hostile takeover of the Republican party.

But the latest polls have things looking grim. Senator Cruz is behind Trump in his home state of Texas (easily the biggest Super Tuesday prize, accounting for around half the delegates at stake). Senator Rubio is behind Mr Trump in the latest polls in his home state of Florida. And Governor Kasich is behind Trump in his home state of Ohio.

Mr Trump holds a total lead in delegates, even though states so far have allocated delegates on a proportional basis. In the recent Nevada and South Carolina races, he won nearly every demographic, including evangelicals and (amazingly), Latinos. Only Republicans with college degrees majority oppose him. Even some establishment Republicans are starting to get antsy, and feel like they should back the probable winner. Today, New Jersey governor Chris Christie endorsed Mr Trump. He's also started to pick up a handful of endorsements from members of Congress.

After March 15, the race switches to winner-takes-all, including the Florida and Ohio votes that will be held on that day. If Trump wins those contests, it's hard to see what would stop him winning the Republican nomination — though his path to the White House from that point is by no means clear. Hillary Clinton (who now has a huge leader over Senator Sanders in delegates overall, despite a couple of close races) will be a tough opponent, and there is a possibility conservative who hate Tump more than Ms Clinton will encourage Michael Bloomberg or another right wing candidate to run a spoiler independent campaign.

Free trade, TPP out of fashion

As NBR has previously reported, the NBR has previously reported, the TPP must be ratified by countries representing at least 85% of the GDP of original signatories to come into effect. In practical terms, that means no US ratification, no TPP.

Mr Trump opposes the trade deal on the grounds that China (not a signatory) is using it to somehow manipulate the US, and is strongly protectionist in general. Second-placed Senator Ted Cruz has raised Jane Kelsey-like concerns over the TPP's potential to undermine sovereignty. Third-placed Senator Marco Rubio was pro-TPP but know says he doesn't know how he would vote. Governor John Kasich, running a distant fourth, is the only Republican contender with any hope (and it's a slim one) that supports the deal.

On the Democrat side, Hillary Clinton and Senator Bernie Sanders both oppose the TPP, saying it will hurt local jobs. Despite a couple of close races, Ms Cinton has developed a huge lead in delegates overall, 536 to 83, and has big leads in most Super Tuesday states.

Pundits expect a ratification vote no sooner than December. Congress, taking its cues the presidential race frontrunners, voted for trade authorisation, but is now widely seen to be frontrunners, voted for trade authorisation, but is now widely seen to be hardening against the TPP. Influential Speaker Paul Ryan (a Republican) says he has his own doubts about the trade deal and, more broadly, is not sure if it would pass the House of Representatives (it must pass the House and Senate for ratification). It would certainly be ironic if Democrats — who mostly opposed President Obama's request for trade authorisation, a precursor to getting the authorisation, a precursor to getting the TPP deal done — switched to supporting the deal to undermine a future President Trump. But with their base so strongly opposed to the trade deal, it seems unlikely.

As things stand, Donald Trump, rather than Andrew Little or an Upper Hutt posse, should be John Key's chief TPP concern right now.