Judging by the party conventions, you'd wonder why this election is even close.

In Tampa, despite some unexpectedly amateurish stagecraft, Republicans put on a credible display of unity and resolve. No one could come away doubting that the party very much wants to defeat President Obama in November.

But I think it's fair to conclude that the GOP's emphasis is on "defeat Barack Obama" rather than "elect Mitt Romney." And many of the party's rising stars, judging by their convention speeches, seem to believe it's likely that Romney will lose.

Coming to Charlotte, N.C., I expected to see a party on the defensive. Instead, Democrats orchestrated a convention that felt strikingly focused and spirited. Speakers relentlessly emphasized the "re-elect Obama" side of the equation, relegating "defeat Romney" to second billing. The oratory was superior, the visuals were more telegenic and there were no Clint Eastwood moments.

You can't conclude that just because the Democrats' three-day infomercial was better than what the GOP put on, Obama is going to win. But even if the conventions aren't remotely as important as they once were, they're not meaningless. They do say something, and this year the message for Democrats is decidedly hopeful.

As I said, the GOP did a respectable job. The most obvious missed opportunities came on the final night - not just the Eastwood Incident, but also the failure to ensure that some of those tributes to Romney's character from individuals whose lives he touched aired on the broadcast networks. But none of this amounts to a major disaster.

Thematically, however, there was a meandering quality to the Tampa convention. In large part, this was due to the decision by some of the marquee speakers to spend more time talking about themselves and their accomplishments than about Romney.

I'm talking about Gov. Chris Christie of New Jersey and Sen. Marco Rubio of Florida - both, not coincidentally, seen as potential presidential candidates in 2016 should Romney lose. It was hard to imagine why Christie and Rubio - and several other speakers as well - would give such priority to their own political prospects if they really believed Romney would be occupying the White House for the next eight years.

In Charlotte, by contrast, there was practically no freelancing. Every speech centered on one of two clear themes: Why voting for Obama and the Democrats is right and why voting for Romney and the Republicans is wrong. Self-indulgence and self-promotion were not allowed.
Even one of the most famously uncontrollable speakers of our time, former President Bill Clinton, stayed relentlessly on message throughout a masterful 50-minute speech. Republicans who suspected - or hoped - there might be a glimmer of daylight between Clinton and Obama must have been disappointed.

Clinton's powerful argument for Obama's re-election was constructed like a lawyer's brief. He systematically countered the Romney campaign's main lines of attack -Medicare, welfare, didn't-build-that - and offered a wonderfully succinct distillation of how Democrats see the difference between the two parties: "We believe that ‘We're all in this together' is a far better philosophy than ‘You're on your own.'"

Clinton's embrace of Obama - political during the speech, physical when Obama walked onstage at the end - was complete and unreserved. Might the former president, totally by coincidence, have also begun to lay the ground for a presidential run by Hillary Clinton in 2016? If so, I think he just wrapped up Obama's support.

All right, Clinton is a unique political asset whom Republicans couldn't be expected to match. But frankly, in terms of speechifying, any one night in Charlotte was better than the whole week in Tampa. The Democrats' first evening featured a barnburner from Massachusetts Gov. Deval Patrick, a stemwinder from San Antonio Mayor Julian Castro and a rafter-raiser from first lady Michelle Obama - plus a couple of also-ran speeches that would have been considered rhetorical highlights at the GOP convention.

And for all the talk of an "enthusiasm gap" favoring Republicans, the energy levels inside the two arenas tell a different story. It's not that the Tampa hall lacked enthusiasm, it's that the Charlotte hall seemed absolutely on fire. Maybe it was desperation among Democrats who realize that Obama could possibly lose. Maybe it was the acoustics. Whatever the reason, I don't know anyone who didn't notice the difference.

Conventions don't win or lose elections, but they can help or hurt. This tale of two cities says President Obama has had a very good couple of weeks.

Eugene Robinson is a Pulitzer Prize winning columnist and writes for The Washington Post. He can be reached at eugenerobinson@washpost.com.