David Miliband's latest email this morning to party members - extracted below - demonstrates the concern that they could, and his campaign's final focus on a "unity", cross-factional pitch in response. The "sick and tired" comment would appear to be a rejection of press or political caricatures of "Red Ed" as a "pre-New labour" candidate (as Peter Mandelson put it), though it could perhaps also imply a challenge to his brother's campaign.
Here's his pitch
I will move us on from Blair and Brown - Leadership 2010
I respect both Tony and Gordon deeply. But their time has passed. Their names do not appear on the leadership ballots. And now we need to stop their achievements being sidelined and their failings holding us back.
I'm sick and tired of the caricature that this leadership election is a choice between rejecting or retaining New Labour. It does a disservice to all of the candidates and, even worse, a disservice to the thousands of members who’ve been participating in this contest over the last few months and working hard for years.
To those trying to trash our past and those trying to recreate it, I say enough is enough, it is time to move on.
I joined the Labour Party back in 1983 because I believed then, as I do now, that we are stronger when we stand together. And that has never been truer than when applied to our Party.
I believe that this election is about pulling together all the talents of our Party. It's about teamwork, mutual respect - and a rejection of the tired old Westminster games of closed door briefings, posturing, attack and rebuttal. I want to change the way we do politics.
Because I want to lead a government not a gang, a movement not a machine, where honest debate can be a source of strength, not a sign of weakness.