A Trivial Matter

In thinking about the current race for president, I noticed that we seem to have an unusual number of candidates whose surnames end in vowel sounds: Obama, Giuliani, Huckabee, Romney, Tancredo.

• Only three presidents had surnames that ended with vowel sounds. Can you name them?
• How about the four whose surnames ended with a silent e?
• Sixteen of the forty-two men who have been president have surnames that end in what consonant?
• What is the most common presidential first name? (There are six who share it.)

Answers in the comments section.