For the last couple of months, there has been a parlor game on Wall Street and in Washington about who will become the next Treasury secretary. After all,Timothy F. Geithner has made it clear he plans to be out of that office at the end of the year whetherPresident Obama is re-elected or not.

But there is another wrinkle in the parlor game calculus: Ben Bernanke, the Federal Reserve chairman, is likely to need a successor, too. If Mitt Romney wins the presidency, he has already pledged he will replace Mr. Bernanke, whose term as chairman ends in January 2014, in just over 15 months. However, Mr. Bernanke has told close friends that even if Mr. Obama wins, he probably will not stand for re-election.

That would be a one-two punch, with two of the most important jobs in the nation up for grabs. And over the last couple of years, especially at the depth of the financial crisis, the relationship between the two people in those roles has been increasingly important. They are the equivalent of roles in a buddy movie.

Lots of names are regularly bandied about for both positions. But they are not always thought about in tandem. So here is a field guide to handicapping the next Treasury secretary and Federal Reserve chairman:

The top Democratic name that pops up when discussing the Treasury position is usuallyErskine Bowles, the former White House chief of staff under President Bill Clinton who reinvented himself with his Simpson-Bowles bipartisan plan to reduce the deficit. The business community, on both sides, appear to love the plan and say they love him.

About a year ago, when Mr. Geithner first told the president that he wanted to step down - before the president persuaded him to stick around for another year - Mr. Bowles was at, or near, the top of the list, according to people involved in the process. That may have changed, however: Mr. Bowles has privately criticized the president to business leaders as he has sought to gain support for his plan.

Some of that criticism has made its way back to the president, these people said, so it is unclear how strongly Mr. Obama would support him.

Another, perhaps more intriguing idea has made the rounds: Mr. Bowles as a Romney appointee. Several supporters of Mr. Romney have pitched him and his team on the idea. An appointment of Mr. Bowles under Mr. Romney would be a quick and clever way to show that he wants to reach across the aisle and find bipartisan ways to comprise.

David Fuller's view think Erskine Bowles would be an inspired choice for Treasury Secretary, particularly if Mitt Romney becomes president-elect. It would certainly improve his chances of bipartisan deficit reduction compromise, which would be necessary assuming that Democrats continued to hold the Senate.

Incidentally, when it was first known that Timothy Geithner wanted to step down as Treasury Secretary about a year ago, my recollection is that Jon Corzine, subsequently of MF Global infamy, was the most frequently mentioned candidate.

Whoever wins the Presidential Election on 4th November, my guess is that Ben Bernanke will remain Fed Chairman until his term expires on 31st January 2014, assuming that he does not choose to retire earlier.