pseudo-incumbent
A person who is not in an elected office, but is garunteed to be elected to this office.
In District 11, Rep. A (R) is currently in office. Rep. A(R) chooses not to run in the 2004 election. Mr. B(D) wins his partys nomination for the election. No one from Rep. A(R)'s party runs his office. Since Mr. B(D) is the only one running for the office, Mr. B automatically wins and is a pseudo-incumbent.
pseudo-incumbent
An "elected" official who is running for office again.
If Bush had been elected in 2000, he would be the incumbent. As he is putatively accepted to have won, he is the pseudo-incumbent