Jonathan Chait thinks that if Scott Brown becomes the 41st vote against President Obama’s health plan, supporters could “Go back to Olympia Snowe” to secure the necessary 60th vote. After all, “Her substantive demands have been met.”

Perhaps Chait forgets that Sen. Snowe (R‑ME) — along with Sen. Susan Collins (R‑ME), and every other Senate Republican — voted to declare an individual mandate unconstitutional. During the floor debate, Sen. John Ensign (R‑NV) took the unusual step of raising a constitutional point of order against the bill’s individual mandate. According to the presiding officer:

The question is on agreeing to the constitutional point of order made by the Senator from Nevada, Mr. ENSIGN, that the amendment violates Article I, Section 8 of the Constitution, and the Fifth Amendment.

Snowe’s “aye” vote makes it hard for her to support any bill that includes an individual mandate. If she were to vote for an individual mandate after declaring that such a law would violate the Constitution, Snowe could reasonably be accused of violating the oath she swore to the Constitution upon joining the Senate.

Yet Democrats are unlikely to support any bill that does not include an individual mandate. As President Obama told a joint session of Congress, his plan “only works” if lawmakers force everyone to purchase government-designed health insurance.