The least surprising comeback in US politics is imminent

The spoiler alerts started early - his own.

Donald Trump has been screaming 'comeback' at political rubberneckers from every stage he could find in the two years since he was turfed out of the White House.

Now, we're told, the least surprising announcement in US politics is imminent.

The timing isn't a surprise, as he'll want to see how the Republican party performs at Tuesday's mid-terms - any politician worth an ounce of strategy and self-interest would want to gauge the speed of travel before jumping on the bandwagon.

Timing could also play into something else - the small matter of possible criminal charges.

The US Justice Department has been investigating the Capitol riots and the discovery of classified government documents at Mr Trump's Mar-a-Lago home and resort in Florida.

If Mr Trump is to be indicted, it would be signed off by Merrick Garland, the US Attorney-General appointed by President Joe Biden.

You can see the script already - the one in which Mr Trump is charged and points to a Democrat stitch-up, politically-motivated, to undermine his presidential ambitions.

Experience tells us his claims would have an audience.

A strong Republican showing on Tuesday can only give him a push - and this, in a party that's been reshaped in his shadow.

Trump acolytes - election deniers et al - are threaded through a changed party.

Even members who resist the pull of his politics can't ignore a core of Trump support within their ranks.

Republican candidates, at national and state level, scrambled to receive his endorsement when they stood in primary run-offs; he will feel they owe him.

He will be the big beast in a party leadership contest but there will, likely, be other serious candidates. People like Ron DeSantis, Florida governor, and the man who served as Mr Trump's number two in the White House, Mike Pence.

The challenge for all will be to corral party traditionalists with its fringe elements turned mainstream.

It will be a continuation of the struggle for the heart and soul of the Republican Party - the rules of engagement won't necessarily be "party first".