Joe Lieberman lost his primary, and filed to run as an Independant. Not long ago, Pennsylvania conservatives kicked out 12 state incumbants during their primaries. Losing a primary is almost unheard of, so there's apparently a message here.

My opinion of the matter is simple. To a good portion of the Democratic Party, supporting the war in Iraq is a deal breaker. And to a good portion of the Republican Party, failure to keep an eye on spending is a deal breaker. I'll leave it up to you to decide which deal breaker matters more to you.