Senators Hillary Clinton and Barack Obama released their own spins on last night's debate in memos sent to the media just fifteen minutes apart. The two memos' spin on their candidate's performance says a lot about how the candidates are positioning themselves with just under six months to go until the Iowa caucuses.

Clinton's subject line, "MEMO: Strength and Experience," said it all. Highlighting her response to a question about whether she would meet with foreign dictators, the memo cited a "clear difference" between Clinton and Obama: Obama would hold meetings with dictators without preconditions, it claims, while Clinton "understands that it is a mistake to commit the power and prestige of America's presidency years ahead of time by making such a blanket commitment."

"Answering the commander-in-chief question is the threshold for any presidential candidate," the memo concludes. As an aside, it was notable that so many pundits last night described her performance as "strong," or some variation thereof. Clinton's camp is just fine with that word.

Fifteen minutes later, Obama campaign manager David Plouffe sent an email to supporters touting the Illinois senator's performance. While debate host Anderson Cooper seemed to miss Obama's slightly veiled hit on Clinton, Plouffe reiterates: "[Obama] displayed the judgment that led him to oppose the war in Iraq before it began and reminded the other candidates that the time to ask how we were going to get out of Iraq was before we went in."

Obama's strategists must have concluded that the line was effective. Look for it to become a permanent fixture of his repertoire.

Plouffe ends the email calling on supporters to help "build this movement for change."

Therein lies the difference between the two front-runners: Clinton's bid is based on the premise of a strong, decisive leader ready to begin on day one. Obama frames his as a grassroots movement for change. This week's ABC/Washington Post poll showed a slim majority of Democratic leaners -- 51% to 42% -- preferring a new direction and new ideas in a presidential candidate to strength and experience, presumably indicating that Obama has more room to grow than Clinton might.

But movements can have a difficult time translating into votes. The most recent analogy, much as the Obama campaign doesn't want this comparison, is to Vermont Governor Howard Dean's campaign in 2004. Voters were with Dean's grassroots movement right up until a few weeks before they cast their ballots, when many chose to go with someone who appeared more ready to be president, John Kerry.

Obama's focus on building the movement may work well now, but before Iowa residents caucus or New Hampshire voters head to the polls, his team may choose to focus more on qualities that put him in the "ready to lead" category as much as Clinton's team is.