If neither courts nor house nor statehouses suffice, Trump has other options.
The reality of this election is it was a massive fix by foreign governments and Biden campaign, and there is copious proof of this.
Under either the 14th amendment, or the insurrection act, trump has the right if his voters rights are being stepped on, to call on the military and/or the militia to intervene. the insurrection act is frequently presented by the Mockingbird media as being old, but it was amended in 2008 and was last invoked by George W. Bush and has been invoked by many other presidents. Whether the whole military would respond, might be open to debate, but Trump gets to cut the orders and undoubtedly he has loyal forces. also the definition of the militia as used in this act is all able-bodied males between 17 and 45, and if Trump calls on them pointing out that they are being screwed out of the election, you can bet your bottom dollar a couple million of them will show up with assault rifles. a million bikers for trump showed up in DC for Labor Day weekend just in 2016.
the biggest question about the insurrection act is whether Trump would invoke it, but the Democrats are already drawing up hit lists and making it plain they will subject trump and his family to lawfare if he leaves office, which is exactly the problem that Julius Caesar had which led him to cross the Rubicon. also trump recognizes that if this blatantly stolen election stands, there will never again be a fair election in the US.
the only reason I'm giving this only a .5 proposed belief, is that I doubt it'll get that far.