After creating a candidate in the game simply text edit the file created with the name of the candidate in the DATA folder of the game directory.
This is an easy way to alter starting money, the candidate's qualities, fundraising ability, home state or starting political party.
Alternatively, if you want to edit the candidates already created in the game edit the file called CoreCandidates.CANDIDATE in the DATA folder.
During the game, you can hit Ctrl & M to raise your bankroll. This puts your cash at $5 million, no matter what your money was before. Don't use this if you have above five million or are going for a high score (as it gives you a score of 0 for cheating).
Alternately, you can go into either the CORECandidates or created character file (as described in the attribute cheat) and alter how much money you start with.