(David Brookman/LBJ Presidential Library)
Of the 49 votes cast on behalf of Medicare (Gore amendment) on September 2, 1964, we lost two supporters in the last election -- Senators Keating and Salinger. However, we picked up five new supporters -- Senators Bass, Harris, Kennedy (Robt.), Montoya, and Tydings.

We also had three supporters who missed the vote this year -- Senators Bayh, Hartke, and Kennedy (Ted).

Thus if all our supporters are present and voting we would win by a vote of 55 to 45.

Of course, if we could persuade Senator Russell (who is on the brink) to support Medicare this year our margin should be even greater.

That letter would never be written today. Confidently asserting that any major piece of legislation could pass with 60 votes would be enough to get a political aide fired. The modern Senate requires 60 votes to pass pretty much anything. The exception are bills that can be passed through budget reconciliation, but that process comes with its own limitations and problems. If you don’t know that today, you are not qualified to work in politics.

In Johnson’s time, however, the Senate was not governed by the filibuster. This chart counts “cloture” votes, which are the votes you take to break a filibuster, and thus give us a way to count whether the majority is having to face down a lot of filibusters. Johnson was president during the 88th, 89th, and 90th sessions of Congress. And as you can see, there weren’t many filibusters:

(Data: Congress.gov; Chart: Ezra Klein)

Which is all to say that Alec MacGillis is right: The idea that an LBJ could simply come along and bring Congress to heel is a wishful anachronism. The Senate doesn’t need a great man. It needs better rules.