Originally Posted by ikestoys
That's true of any primary in any year.
Gotta disagree with you there, Ikes.
The parties and their constituencies are different. You've surely seen the many polls showing that Democrat voters value "compromise" more than "standing up for principles," whereas it's the reverse for Republican voters.
One reason that Obama beat Clinton is that he projected a more moderate tone; and certainly, his campaign - even in the primaries - made heavy use of the idea that he could be post-partisan and work with the GOP.
Bill Clinton and Jimmy Carter similarly were hardly the loudest firebrands when they ran in primaries.
"Being the voice of reason" and "willing to work with the GOP" is a selling point to a notable segment of the Democratic primary-electorate.