If we're talking about rigged political systems, the US system is heavily rigged in favour of Republicans. It's way more than just the voter suppression techniques used in some Republican controlled areas, it's the fact that Wyoming (and many other small Republican states in terms of population) have the same the number of Senators (two) as California, despite the latter having a population seventy one times as big as the former.
This means that the Republicans will almost always control the senate, which either means gridlock in federal government (given the current unreasoning hostility of Republican to all things Democrat) or else - and god forbid Trump should win - an easy time for any Republican president.
Some may think this a wild statement, but I honestly think that a Trump presidency, combined with a Republican Senate and House, would have a good chance of spelling the end for US democracy in any meaningful sense. Laws would be enacted to bring the press and media closer to Trump's heel, the Supreme Court would be gradually filled with 'Yes Men' holding extreme views not previously witnessed within that body, voter suppression techniques would be aided and abetted by the federal government, voting boundaries would be rigged in favour of Republicans, government officials would be purged of all non-Trumperites ... and so on.