Twenty-second Amendment to the United States Constitution
Some argue that the 22nd Amendment and 12th Amendment bar any two-term president from later serving as vice president as well as from succeeding to the presidency from any point in the presidential line of succession. Others contend that the original intent of the 12th Amendment concerns qualification for "service" (age, residence, and citizenship), while the 22nd Amendment, concerns qualifications for "election", and thus (strictly applying the text) a former two-term president is still eligible to "serve" as vice president (neither amendment restricts the number of times an individual can be elected to the vice presidency), and then succeed to the presidency to serve out the balance of the term (though prohibited from running for election to an additional term).
Lyndon LaRouche U.S. presidential campaigns
He ran even though his home state of Virginia is one of a handful of states which still has lifetime denial of the vote to felons, which can be overturned only on appeal to the governor. (Neither the Constitution nor federal statute law requires presidents to be registered voters.) The Democratic Party did not consider his candidacy to be legitimate and ruled him ineligible to win delegates. He gained negligible electoral support. He was endorsed by two Democratic state representatives, Erik Fleming of Mississippi and Harold James of Pennsylvania, though Fleming later called the endorsement "the worst mistake of all." LaRouche was not one of the major candidates invited to the primary-season debates, although he did participate in some alternative forums for minor candidates.