Is there a 0% chance of this happening, or a .01% chance?
I guess there's a slightly greater chance of this than there is of RFK Jr. becoming President, and who knows... I did laugh at Trump's chances before he won. It's a nice idea.
He's bucked it on some things and done more than most to, say, make average Republicans more anti-war and because of that having it be more acceptable for Republican politicians to take similar stances. He was famously instrumental in affecting the last administration's foreign policy on some things, etc. He usually votes the right way, including against leadership.
However, he has made me cringe whenever he's given praise to people like Trump and made more pragmatic concessions than I'd like when it comes to things like phrasing.
I know plenty of libertarians who support Trump, actually. I'm not one of them, but there is an argument that isn't crazy for doing so.
And in terms of leader of Senate Republicans, literally every one is gonna have some support for the Republican President or presidential nominee.
The libertarian case for Trump starts with a premise I reject... That the case is only between the two candidates that can win in an electoral sense. In that case, we're talking Trump/Biden and Trump/Hillary, and not considering, you know... Johnson or Jorgensen or NOTA.
So... Trump v. Biden. Trump jacked up spending to unprecedented levels in order to deal with a national emergency, something like $6t of spending with only $4t of tax revenue. Biden did nothing to bring it back down to pre-pandemic levels, and had even tried to increase it (above emergency levels even after the emergency had passed). Trump was the first president of my lifetime not to get us into a new war. Although Biden got us out of Afghanistan, he then pivoted to risking war with Russia over Ukraine. On criminal justice, Trump gave us the first step act while Biden had been a huge drug warrior for literal decades. On civil rights, Trump might have racist tendencies, but he was running against someone who literally opposed bussing because he didn't "want his children to attend a racial jungle". Assuming by fascism one means big business and big government working hand in glove, Biden acted more like a fascist. Although Trump chanted "lock her up", he didn't try to, while he's running against lawfare and political prosecutions directed his way currently. He's been more skeptical of alphabet agencies (CIA, FBI, etc), even if it was primarily just because they worked with social media companies to censor speech that could help him to decide elections. He was willing, as President, to talk to America's enemies rather than refusing to. He succeeded in getting the Abraham accords passed, by stepping over the precondition thing.
I don't buy the argument that a libertarian should support Trump. I didn't and wouldn't. But there's plenty of arguments for him over Biden or Hillary.