So, Garrett Graff (who) on CNN says Pompeo could be next in line...

[Jim__]

17. Presidential Succession Act of 1947 says Speaker of the House.

From wikipedia:

To provide for the performance of the duties of the office of President in case of the removal, resignation, death, or inability both of the President and Vice President.

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That

(a)

(1) if, by reason of death, resignation, removal from office, inability, or failure to qualify, there is neither a President nor Vice President to discharge the powers and duties of the office of President, then the Speaker of the House of Representatives shall, upon his resignation as Speaker and as Representative in Congress, act as President.

(2) The same rule shall apply in the case of the death, resignation, removal from office, or inability of an individual acting as President under this subsection.

(b) If, at the time when under subsection (a) a Speaker is to begin the discharge of the powers and duties of the office of President, there is no Speaker, or the Speaker fails to qualify as Acting President, then the President pro tempore of the Senate shall, upon his resignation as President pro tempore and as Senator, act as President.

...