So, I'm sure it's been asked before but what if Francis I became HRE instead of Charles V?
Okay, so I've been brainstorming and I came up with the most likely scenario, in my mind, to accomplish the task. Though, give me some slack cause I ain't the best with HRE history.
Francis I plays up the fact that he's willing to take on some Protestants, this gets him the votes of Hermann, Archbishop of Cologne and Albert, Archbishop of Mainz.
Now, Joachim I, Margrave of Brandenburg, sides with Albert, his brother, and votes for Francis. George the Bearded, though a member of the Order of the Golden Fleece, votes for Francis when he promises to pay for the Saxon loss of Friesland to Burgundy and then some, they let the territory go for only 100,000 florins.
So that's four, which is the amount needed.
If there are more than a few glaring holes just point 'em out, like I said, the HRE is my weak spot when it comes to European history, so this was just my best try.
And now comment on what the effect of Francis I coming to power instead of Charles V is.