Vice President Dick Cheney's health problems have triggered speculation that he may be forced to step down, a move that could potentially throw the Republican 2008 presidential nomination race into disarray.
In the event of the vice presidency becoming vacant through resignation or death, the Constitution requires the president to nominate a vice president who must be confirmed by majority vote of both houses of Congress.
Bush would find it difficult to get a Democratic-controlled Congress to approve a conservative nominee, analysts say. At the same time, neither of the leading GOP 2008 presidential aspirants - former New York City Mayor Rudy Giuliani or Sen. John McCain of Arizona - would be eager to be seen as President Bush's heir apparent, should he tap either of them for the job.
If, on the other hand, Bush were to replace Cheney with Secretary of State Condoleezza Rice - a move analysts consider not unlikely in the event of a vacancy - Rice would almost certainly accept the position only if she was also prepared to run for president in 2008.
I still have a Condi bumper sticker on my car...