Why the GOP sucks:
The GOP has embraced the crazies on the far right side of the aisle. For the most part they refuse to accept the reality of evolution. Global warming is more about politics than about science. There are too many on the right who are hypocrites - especially when it comes to family values and gay rights.
They suck.

Why the Dems suck:
They often come across as elitists (do as I say, not as I do). They want to spend lots of money on social projects, yet when those projects don’t work the only answer is ‘we need more money’. Way too often money allocated for those social projects ends up in someone’s pocket. They want bigger government, when in reality the government just does a horrible job at getting things done at a reasonable cost.
They suck.

IMHO.