It may take weeks to find out whether the decision by the Colorado Supreme Court to declare Donald J. Trump ineligible to be on the state primary ballot will hold.

But its short-term political impact was clear by the time Mr. Trump stepped off a stage on Tuesday night in Iowa, where he learned of the ruling shortly before a scheduled campaign rally began.

Allies of the former president posted on social media that the ruling was an indignation, one that the U.S. Supreme Court needed to rectify.

Colorado’s top court found that Mr. Trump had incited an insurrection on Jan. 6, 2021, and should be barred from the ballot under the 14th Amendment to the Constitution. Mr. Trump could remain on the ballot regardless — the Colorado justices put their ruling on hold as appeals are likely to proceed — but Mr. Trump’s team was hardly dwelling on that detail.

Even if Mr. Trump remains on the ballot, any court having said that Mr. Trump incited an insurrection will be used against him in a general election, in ways his advisers know could be damaging. But the Republican primary is different. Officials with Mr. Trump’s rival G.O.P. campaigns privately feared that the decision would be seen as an overreach by Democrats, one that could bolster his current lead among Republicans in the Iowa caucuses on Jan. 15, and in the primaries immediately after.

For years, events that would thwart other politicians have at best slowed Mr. Trump’s forward motion, with the prominent exception of his loss in the 2020 election to Joseph R. Biden Jr. Throughout 2023, Mr. Trump has exploited as political fodder events that would have sunk other candidates — such as being indicted four times, on 91 felony charges — with a Republican electorate that has been told Democrats are threatening their way of life.

Since March, Mr. Trump has perfected a playbook of victimhood, raising campaign funds off each indictment and encouraging Republican officials to defend him. Many — including some who are fearful of Mr. Trump’s hold on the party’s core voters — have obliged.

Democrats and the comparatively few Republicans who want to see Mr. Trump stopped have described his criminal legal travails as of his own making, and tried to highlight the details of the crimes he is accused of committing. They vary widely and include charges he conspired to defraud the United States with months of election lies aimed at subverting the transfer of power as well as charges stemming from mishandling classified documents.