A new Time poll on Thursday added ammunition to Barack Obama's case that he is the more electable Democratic candidate. In head to head match-up against the presumptive GOP nominee John McCain, Obama scores a 48% to 41% victory, while Hillary Clinton produces only a 46% to 46% draw. But while Barack Obama certainly has an electability argument to make, his misguided framing of that advantage does his campaign - and the Democratic Party - harm.
The Time surveys suggests both what Barack Obama has claimed and primary voters to date have expressed at the ballot box. That is, Obama's edge comes from independent voters:

The difference, says Mark Schulman, CEO of Abt SRBI, which conducted the poll for TIME, is that "independents tilt toward McCain when he is matched up against Clinton But they tilt toward Obama when he is matched up against the Illinois Senator." Independents, added Schulman, "are a key battleground."

You can't blame Obama for asserting - with good reason - that he is uniquely positioned to attract new voters, younger Americans, independents and even some Republicans. It's how he's making that argument, however, leaves a lot to be desired.
On several occasions, Obama's rhetoric has suggested his defeat would jeopardize Democratic Party unity. During a January 22 interview, Senator Obama hinted he might take his toys and go home if failed in his quest for the Democratic nomination:

"I think there is no doubt that she has higher negatives than any of the remaining democratic candidates. That's just a fact and there are some who will not vote for her...
...I have no doubt that once the nomination contest is over, I will get the people who voted for her. Now the question is can she get the people who voted for me? And I think that describes sort of one of the choices that people have, just a practical choice, as they move forward."

Even during the lovefest that was the January 31 CNN debate in Los Angeles, Obama pressed the point:

"I believe I am attracting new voters and independent voters in a way that senator Clinton cannot do. That's particularly important if Senator McCain is the nominee. I'm confident that I will get her votes if I'm the nominee. It's not clear that she would get my votes if I were the nominee."

And on Sunday, Senator Obama on CBS Face the Nation repeated his case, though in a softer tone:

"There is some history there, not all of Senator Clinton's making, but I don't think there's any doubt that the Republicans consider her a polarizing figure. Now, keep in mind, I don't expect, should I become the Democratic nominee, that I'm going to be immune from some of the attack that I think the Republican spin machine is so accustomed to.
But what we have found - this is true in Illinois, when I was running for the United States Senate, I think it's going to be true nationally - is that the tone that I take, the ability to disagree without being disagreeable, the willingness to listen to Republicans about some of their ideas, even though I may not agree with all of them - I think that creates a different climate. And I think that we can attract independents and Republicans in a way that Senator Clinton cannot."

Unfortunately, Michelle Obama too has gotten into the act. Appearing on Good Morning America on Monday morning, Mrs. Obama hesitated when asked how her own support would translate to Hillary Clinton in the general election:

ROBERTS: So what if Senator Clinton defeats her husband, becoming the first woman nominee. Could you see yourself working to support the first woman nomination?
OBAMA: I'd have to think about that. I'd have to think about that, her policies, her approach, her tone.
ROBERTS: That's not a given?
OBAMA: You know, everyone in this party is going to work hard for whoever the nominee is. I think that we're all working for the same thing. and, you know, I think our goal is to make sure that the person in the White House is going to take this country in a different direction. I happen to believe that Barack is the only person who can really do that.

Barack Obama's electability argument is strong, but not unassailable. In Nevada and California, he was drubbed by Clinton among Hispanic voters. With his past support for immigration reform, John McCain may be the only Republican left capable of a respectable showing among Hispanics. Obama lags, too, among older voters.
As this tight Democratic race moves on, the rhetorically gifted Barack Obama needs to hone his case that he's more electable. Tell the American people you can attract new voters to the Democratic tent, but promise that you'll do everything you can to keep them there whether you're the nominee or not. Don't make veiled threats that your supporters will walk if you're not running. This November is simply too important for the Democratic Party - and the American people.
UPDATE: The latest CNN data adds more support to Obama's electability claim. While the CNN survey shows Hillary Clinton leading John McCain by 3 points (50% to 47%), Barack Obama enjoys an 8 point margin (52% to 44%). Memo to the Obama campaign - use it wisely.