Does Inter-Party negativity lead to demise?

[Tobina+1]

OK, so I couldn't come up with a good subject line for this one (too much pressure from all of Warph and Waldo's good subjects).
Bascially, my question is... do you think that during an election, does the negative campaigns within the same party against each other ultimately effect the outcome of the entire race for that party?
Or in simpler terms... after months and months of Clinton bashing Obama on all aspects of his campaign, do you really think that her supporters will be willing to back him now?  Haven't parties learned by now that they should band together early to win the entire election rather than wait until the last 5 months?  This same question can be asked of both parties, depending on the election year.
Or are the party lines becoming more gray now, and people won't vote for someone just because they are "Democrat"?

[Wilma]

The only time I have ever voted party was in the primaries when I wasn't allowed to vote for whom I thought was best.  In general elections I vote for the candidate I think is best no matter what their party affiliations are.  In the months of campaigning leading up to the convention, I mostly ignore what is being said.  After the convention, it is easier to determine who the best person for the job is.  If there is something bad about the candidate it is going to come out.  You can count on that.