If, Hypothetically, Two Senate Seats Were to Open Up . . .

With national polls suggesting that the Democratic ticket of Barack Obama and Joseph R. Biden Jr. has moved into a clear lead in the race for the White House, party strategists are beginning to look ahead to who might replace each man in the Senate if they do prevail on Nov. 4.

Both appointments would be made by Democratic governors. In Illinois, that would be embattled Gov. Rod Blagojevich; in Delaware, it would almost certainly be outgoing Gov. Ruth Ann Minner. (Minner will be a lame duck because of term limits, but her successor will not be sworn in until Jan. 20 -- the day of the inauguration of the next president and vice president. Biden would almost certainly resign his seat before that date.)

Whom would Minner and Blagojevich pick? And would their selections be "caretakers" -- serving out the two years between 2008 and 2010, when a special election will be held for the seats -- or would they be choices who would seek to stay in the office for years to come? The jockeying is underway.

In Illinois, the four most commonly mentioned names are those of Reps. Jesse L. Jackson Jr. and Jan Schakowsky; state Senate President Emil Jones Jr.; and Tammy Duckworth, the head of the Illinois Department of Veterans Affairs and an unsuccessful candidate for Congress in 2006.

Jackson has been the most overt about his interest in the job, telling Congressional Quarterly in August: "I wouldn't say no if asked." But Blagojevich and Jackson don't have the warmest of relations -- due at least in part to a long-running feud in state Democratic circles over the construction of an airport in the southern suburbs of Chicago.

Jones, who is retiring next year after more than three decades in office, has engaged in something of a co-governorship with Blagojevich over the past several years and, at 72, might be more of a caretaker than a long-term answer in the Senate.

Jackson and Jones are African Americans -- a factor that may weigh heavily on Blagojevich's decision, given that he would replacing Obama, the lone black senator.

But it is Duckworth who has emerged as the front-runner in recent weeks. She was appointed to her post by Blagojevich after a narrow loss to Rep. Peter Roskam (R) in the 6th District in 2006. Duckworth's compelling personal story -- she was a Black Hawk helicopter pilot in Iraq who was shot down and lost her legs and the use of one arm in the crash -- coupled with her close relationship with the governor (he held an event honoring her at the Democratic National Convention in Denver) has created rampant speculation that Duckworth would be the choice.

In Delaware, the machinations are complicated by the recent call-up and deployment to Iraq of Attorney General Beau Biden, the senator's son. The younger Biden, who was deployed Sunday for a year-long tour, was widely seen as the heir apparent to his father's seat whenever the elder statesman decided to vacate it.

With Beau Biden in Iraq for the next year, Minner could come under pressure to appoint a caretaker to the spot so the junior Biden could run in the special election in 2010. If so, Minner herself might not be a bad pick -- perhaps seeing a two-year Senate stint as a capstone to a career that has included stints in both houses of the Delaware legislature as well as eight years a lieutenant governor and then governor of the First State. It's not clear, however, whether Minner, who would be 74 when sworn in to the Senate, is interested in coming to Washington.

If Minner doesn't appoint herself, the leading name would probably be that of Lt. Gov Jack Carney, who was beaten in the Democratic gubernatorial primary this year by state Treasurer Jack Markell. Minner and Carney have been close political allies for a number of years, and the governor endorsed his unsuccessful primary candidacy.

For Republicans, who have grown increasingly less competitive in the state over the last decade, Rep. Mike Castle may be their last best hope to win a Senate seat. Castle served as governor of Delaware from 1984 to 1992 and has been in the House since. He would be -- by far -- Republicans' strongest candidate in a 2010 open seat race.