How Many Senators Does It Take To Impeach A President? It's Very Specific
Under the U.S. Constitution, at least 67 senators must vote in favor to remove an impeached president from office. Article I of the Constitution states that while the House has the "sole power of impeachment," the Senate has the power to "try all impeachment." The president, vice president, and civil officers are all subject to impeachment, but in a presidential impeachment, the Constitution is specific about the process: the Chief Justice of the Supreme Court presides over the trial, and it takes a two-thirds majority to remove a president from office. Given the 100 members of the Senate, this works out to 67 votes (and no, the vice president cannot act as a tie-breaker in this one). The Senate vote marks one of the last steps in the impeachment process, and without the majority vote, the president cannot be removed from office.
http://www.elitedaily.com/p/how-many-senators-does-it-take-to-impeach-a-president-its-very-specific-19365512
...been hearing all morning that they only need 51 votes. Even Rush said it. Dunno what's correct. I shall pursue this valuable knowledge unless one of you guys beat me to it.

Liberals are like a "Slinky". Totally useless, but somehow ya can't help but smile when you see one tumble down a flight of stairs!