Donald Trump just had the best 24 hours of his reelection campaign. But it might come back to bite him.

• Donald Trump is wracking up wins after Joe Biden gave a dismal debate performance.
• The Supreme Court also issued two conservative rulings hours after the debate.
• But Trump's seeming wins this week could fizzle out by November. 

Former President Donald Trump is back on top — at least for now.

The Republican nominee secured a spate of political wins this week after President Joe Biden delivered a disastrous first debate performance, and the Supreme Court handed down two Trump-friendly decisions.

But Trump's Thursday night and Friday morning victories are far from permanent, and aspects of this week's ostensible wins could fizzle in the long run.

Biden's big blunder

Political experts and pundits seem to agree that Trump also performed poorly in the Thursday debate. He lied several times, failed to articulate his plans and policies, and once again boasted about his golf swing.

But few were focused on Trump's faux-paus in the debate's aftermath. The focus was on Biden's raspy voice and seeming memory gaffes, which only exacerbated growing concerns about the 81-year-old president's age and fitness.

Throughout the debate, Trump managed to inject some of his notorious zingers, including after one particularly incoherent Biden ramble, saying, "I really don't know what he said at the end of that sentence. I don't think he knows what he said either."

Democrats responded to the debate with abject panic as some Biden loyalists started pushing for him to step down. The resulting liberal frenzy is at least marginally good for Trump, according to Christian Grose, professor of political science and public policy at the University of Southern California.

"Trump is benefiting only in the sense that Biden did not benefit," Grose said.

Most voters, however, are already decided. While the debate might have swung undecided Americans further toward Trump, Grose said Biden's poor performance is unlikely to sway Democrats toward the Republican nominee in today's partisan age. Biden may have lost himself some votes, but it's not evident that those will bolster Trump's base, Grose said.

"Those who support Donald Trump will continue to support him in November, no matter what happens until then. Those that do not, will not," said David Triana, a public relations consultant focused on legal figures. "The question there remains: will they vote for Biden or stay home?"

The early nature of this first debate could, however, end up playing in Biden's favor. Public recall tends to be short, and there is still ample time between now and November for Biden to try to change the narrative around his age — especially amid Trump's ongoing legal woes, Grose said.

"Something terrible happens to one of these candidates once every two weeks — usually Trump," Grose said.

SCOTUS surprises

Less than 24 hours after the debate, the Supreme Court handed down two major decisions, which, at first glance, appeared to be more good news for Trump.

The top court overturned the Chevron doctrine, a decades-old legal precedent that required courts to defer to federal agencies' interpretations of congressional statutes when reasonable. Conservatives long had their sights set on overturning the doctrine, which they argue granted too much power to the executive branch.

In a separate 6-3 decision, the Supreme Court also narrowed charges for several January 6, 2021 rioters, ruling that the obstruction statute used to prosecute the defendants was employed too broadly by the Department of Justice.

Both decisions are a reminder of the outsize role Trump has played in shaping the modern court. During his first term, he appointed three conservative justices who helped swing the court further right than it had been in many years.

The January 6 case also has positive personal implications for Trump, who also faces a federal obstruction charge in Special Counsel Jack Smith's case. On Friday, legal experts told Business Insider that the decision was good news for Trump's legal prospects.

But the personal benefits Trump may reap from the Supreme Court's decisions could have unwanted political effects on his campaign, Grose suggested.

It could remind voters unhappy with the Supreme Court's conservative drift that another Trump term could mean more Trump SCOTUS appointees.

Much of Biden's platform revolves around his claims that he alone can protect democracy from the dangers of a second Trump term. Undecided voters with strong opinions on abortion and January 6 could be turned off by Trump's Supreme Court appointees and their increasingly conservative rulings, he suggested.

Should the court rule in favor of Trump's presidential immunity case next week, voters could be more inclined to believe Biden's narrative about democracy needing to be saved, Grose said.

Many undecided voters are also particularly concerned with a candidate's character, and Trump's refusal to acknowledge responsibility for his crimes could come back to bite him with independents — especially if the Supreme Court grants him broad immunity, Triana said.

But ultimately, it's just too soon to say how this week's events will impact November, Grose said.

"We just have to wait and see how the polls shake out," he said.