"We are what we say we are not."
Whenever a Democrat tells the public what his party "is not" he's revealing to them what it is. John Kerry fell into this habit often, saying the Democratic Party "was not" weak on national defense which only succeeded in reminding voters of the party's historic uselessness on security issues.
On Meet the Press last Sunday, Howard Dean returned to this poisoned well, protesting a little too much at what the "party was not." He said, "We're not the party of abortion," and "We're not the party of gay marriage." An appropriate response from moderator Tim Russert would have been a loud and sustained chuckle.