With most of official Washington and Chicago abuzz with what seems to be White House Chief of Staff Rahm Emanuel's inevitable run for mayor of his home town, the focus has also inevitably turned to who will replace Rahm. Some in Washington have even asked, can the scrappy, formidable former congressman really be replaced?

"Yes" was the short answer from his long-time friend and colleague David Axelrod, senior adviser to the President, who told NBC's The Today Show on Wednesday, "He is valuable to the president, but no one is indispensable. If he does decide to go in that direction there are many to fill in breach."

But Axelrod can cross one name off his breach list, that of Sen. Mark Warner, D-Va., who has been touted by a number of politicos as a possible replacement. (He is, afterall, a very successful former businessman.)

His spokesman, Kevin Hall, tells Fox emphatically, "It's not happening. Sen. Warner was hired by the people of Virginia to work for them, and that is what he is going to keep doing."

And after all , the popular former governor of Virginia was once thought to be a strong candidate for the Oval Office, himself, and he still could be. If the Democrats lose big this fall, as experts are predicting, it might not be wise for the senator to be in the middle of that fight, tussling with a strengthened GOP opposition.