ST. LOUIS -- The best question asked of a vice presidential candidate in a broadcast television setting on Thursday night did not come from debate moderator Gwen Ifill.
It came from CBS News anchor Katie Couric, who continues to release bits and pieces from her interviews with Republican vice presidential nominee Sarah Palin.
In a segment aired Thursday night -- a few hours before Palin would debate Democrat Joe Biden -- Couric asked the Republican contender to name the vice president she admired most.
Palin's response? "My goodness, I think those who have gone on to the presidency," said the governor, without blinking.
Palin expressed particular regard for former President George H.W. Bush.
Why? Because of Bush's "having kind of learned the ropes in his position as vice president and then moving on up."
More than any Q&A during the debate, this question and its answer actually revealed something about Palin.
The governor may be running for vice president this year.
But she is, as well, running for president.
If McCain wins, she'll have to wait awhile.
If McCain loses, watch for Palin to announce her candidacy for the 2012 Republican presidential nomination right around the time that her esteemed running-mate concedes.
There is much about ambition that is admirable.
But Palin's ambition, like her secretiveness and frequent abuses of the elected positions she has held, brings to mind another former vice president who became president: Richard Nixon.