Washington (CNN) - There is now a good chance that White House Chief of Staff Rahm Emanuel will step down from his post as early as October to focus full-time on running for Mayor of Chicago, according to two people close to Emanuel.
One person close to Emanuel added that the highly-respected White House Deputy Chief of Staff Pete Rouse is the favorite to take over as chief of staff on a temporary basis in order to give President Obama more time to find a long-term replacement. But other people close to the situation said it is too early to determine who will replace Emanuel short-term or long-term because the process is so fluid at this point.
Rouse served as chief of staff in Obama's Senate office and is known to have the President's trust. Democratic officials have told CNN that Rouse, who is known for not relishing the spotlight, has suggested he does not want the chief of staff post long-term. But it is expected he would be willing to help the White House get through a transition period and then have an influential role in helping to select the full-time replacement.
The people close to Emanuel confirmed a report in Time magazine, CNN's sister publication, that Emanuel could leave as early as next month in order to devote his full energies to mounting a bid to replace retiring Mayor Richard M. Daley. There is some urgency to the situation because candidates must gather 12,500 signatures by Nov. 22 ahead of the Feb. 22 primary in the race.
But the people close to Emanuel stressed to CNN that the chief of staff has not made a firm decision yet to run for Mayor, though these sources did indicate that the former Congressman from Chicago has all but decided to take the plunge.
The sources familiar with the situation said that once Emanuel does make a firm decision the process will move very rapidly because the chief of staff realizes that he has a lot of work to do to get a campaign off the ground.
Emanuel is also very sensitive to making sure he leaves the White House in good hands given the critical midterms that are fast approaching, as well as other transitions expected to happen after the election. For example, the President's chief economic adviser, Lawrence Summers, announced Tuesday he will be leaving at the end of the year and the search for his replacement is under way.
A key date on the calendar to watch is when the Senate decides to adjourn before the election, according to people close to Emanuel, because he is heavily involved in pressing to get some of the President's initiatives on the agenda before the Senate leaves.
The Senate was originally scheduled to adjourn on October 8, but Senate Democrats say they may now leave as soon as the end of next week which would be the beginning of October.
But there is also a realization within the administration that is never a good time for a chief of staff to leave given the constant press of business, so Emanuel is going to have to leave sometime soon if he is to give a Mayoral run his full attention.
CNN has previously reported that possible fulltime replacements in the mix include top White House aides Tom Donilon, Phil Schilirro and Ron Klain.