Is the Democratic Convention always first? If so, why?

Whichever party doesn’t occupy the White House goes first. That’s been the case since 1936. Don’t know why, though

update based on further research:

Apparently, this scheduling custom has never actually been formalized; there’s no written rule or agreement that this should be so. The traditional explanation is that the challenging party requires more time to prepare the campaign, so they kick off the campaign earlier, but the value of this reasoning has been frequently called into question.

There was an attempt in the 1956 election cycle to reverse the traditional order, but calendar jockeying among the parties resulted in the order being maintained anyway.

I guess this explains why there is little time between conventions. The dems pushed it back far, and then the Republicans fit theirs in after, but had to do it right after, in order to take advantage of the time left before the election.

Is it an advantage to go last?

Studies seem to indicate that the “bounce” factor is not that significant (about a 6% boost) nor long-lived.

A more significant factor relates to campaign finance laws. The financing of a candidate’s nomination campaign is considered separate from the financing of his general election campaign. If a candidate accepts public financing for the general election, he is subject to spending caps.

That spending is only calculated from the time the nomination is made, however. If a candidate can postpone his nomination as long as possible, that’s that much longer that he can spend campaign dollars without them counting against the spending caps.

In this particular election, this will not be a disadvantage for Obama, since he has declined public financing and so won’t be subject to spending caps.

And, of course, since McCain is going the public funding route, he wants to delay as long as possible, in order to spend other money first, and then get the public money to go as far as possible.

Yep.