The simple explanation for any centrist drift by Kerry is obvious: this is how one wins elections. Nader polls about 4%, while only about one-third of voters are declared Democrats. Thus, there are many, many more "centrist" independents (and Republicans) among non-Democrats than left-leaning Naderites.
Where would you look for votes if you wanted to be elected President of the US?
One press report linked Kerry to the Democratic Leadership Council, despite the Joe Klein column from a few weeks ago pointing out that the DLC is almost completely marginalized in this election cycle. Should we be surprised that the DLC now supports Kerry?
Where else can the DLC go?
As David Corn wrote in The Nation just a few weeks ago, Kerry has not overtly tried to woo the DLC. He's trying to win as many votes as possible, but he's not retreating from his long-time positions opposed by the group:
When Clinton in 1992 wanted to prove he was a "New Democrat," he promoted welfare reform and showcased his devotion to the death penalty. Kerry has done nothing so dramatic. (He is an opponent of capital punishment.) He has talked about deficit reduction and supported certain tax cuts (while opposing breaks for the wealthy). He has straddled the line between the DLC and the traditional Dems without causing much fuss. To triumph in the battleground states, is it better for Kerry to be a populist firebrand who excites the Democratic base or a center-chaser who nabs swing voters? This is more a question of theology than a correct-or-incorrect choice.Corn then quotes one of Kerry's advisors, pointing out that the candidate has a long record of supporting equality and justice for working families.
There are numerous other Kerry virtues:
Kerry wants to overturn the Bush tax cuts for the wealthiest Americans.
He has called for a meaningful increase in the minimum wage. Indeed, he has a strong record on workers/jobs and a 90% career AFL-CIO vote index record.
He wants to significantly increase health care coverage.
Kerry has a genuinely good record on the environment and will strengthen, rather than rollback, past protections.
The complete plan for the first 100 days is on-line: National Education Trust Fund, end the "Era of Ashcroft," etc.
He hasn't called for withdrawal from Iraq, nor for pulling out of global trade agreements, but his views on these questions are clearly better than the position of Bush and the Republicans.
As Kevin Drum blogged, Dick Armey's group, Citizens for a Sound Economy, is trying to get Nader on the ballot in Oregon. Armey used to hold a Republican leadership position in the House of Representatives.
In short, Republicans recognize that helping Nader is tantamount to helping Bush.
If the left supports Kerry in 2004, there's every reason to believe that we can help shape his governing decisions. However, if the left abandons Kerry by "sitting this one out" or voting for Nader, then it really shouldn't be surprised if Kerry ignores their views more often than not.