According to an interesting article on the Volokh Conspiracy blog at the Washington Post, many state ballot access laws will prevent whoever loses the Republican presidential nomination at the July 18 to July 21 convention from effectively running as a third-party candidate.

As a result, if Donald Trump is thinking about running as a third-party candidate, he will likely need to make a final decision by mid-April at the latest.

The filing deadline for independent presidential candidates in Texas is coming up quickly – May 9 – and the candidate will need “1% of the total votes cast for all candidates in the previous presidential election,” or about 80,000 signatures, to be on the ballot.  In other words, last-minute decisions are doomed to fail.

Other states with filing deadlines before the end of the GOP convention include North Carolina (June 9); Illinois (June 27); Indiana and New Mexico (June 30); Nevada (July 8); Georgia (July 12); Delaware, Florida, Oklahoma, and South Carolina (July 15); and Michigan (July 21).

A host of other major states have deadlines soon after the convention, complicating efforts to get on the ballot if a decision is not made until that time.

If primary voting trends continue as the polls suggest, Trump will be winning the large majority of states by mid-April but will not likely have a majority of delegates – and if the establishment holds the line against him, he may arrive at the convention with 70% or more of the states won but only 40% of delegates.  The establishment would then unite against him – Cruz/Rubio ticket? – and Trump would lose the convention and not have the “consolation prize” of a serious third-party run as his final option.

Thus, the GOP nomination may be officially decided within a month, with Trump going third party, which would leave Cruz in the driver's seat for an easy win at the convention – and a general election three-way showdown among Hillary Clinton, Trump, and Cruz.  This would ensure a Clinton landslide victory.