I believe his defense lawyer.
The money swap was legal. Presumably the jury chose to ignore that one facet of money (PAC side) did not make it to candidates whereas the other facet (Corporate side) was substituted.
If both facets had made it to candidates, then Delay would be guilty. But it was clearly a case of accounts receivable from PAC being swapped for Corporate cash on hand, which is legal.
I suspect the jury looked at one fact that corporate cash was used to fund candidates and ignored the swap. They chose to ignore the larger context.
The technicality will likely be that admissible evidence was not considered by the jury and that the instructions to the jury were in error that led them to convict.
He should get a mistrial and may get a new trial or have the charges dropped. Apparently his lawyer proved that the net money was from PAC sources via a legal swap.
If I have the facts right from what I have read, this trial was a waste of court time.