By these means, and by the lavishness of his expenditure on public entertainments as aedile, he acquired such popularity with the plebs that he was elected pontifex maximus in 63 B.C. against such distinguished rivals as Q.
Cicero states that from the earliest period down to the pontificate of Publius Mucius Scaevola (c. 131 B.C.), it was usual for the pontifex maximus to record on a white tablet (album), which was exhibited in an open place at his house, so that the people might read it, first, the name of the consuls and other magistrates, and then the noteworthy events that had occurred during the year (per singulos dies, as Servius says).
Vacancies in the body of pontifices were originally filled by co-optation; but from the second Punic War onwards the pontifex maximus was chosen by a peculiar form of popular election, and in the last age of the republic this held good for all the members.
Two individuals are of some importance: (i) Marcus Cornelius Cethegus, pontifex maximus and curule aedile, 213 B.C. In 211, as praetor, he had charge of Apulia; later, he was sent to Sicily, where he proved a successful administrator.
Ahenobarbus was elected pontifex maximus in 103, consul in 96 and censor in 92 with Lucius Licinius Crassus the orator, with whom he was frequently at variance.
In 63 B.C., at Caesar's instigation, he prosecuted Gaius Rabirius for treason; in the same year, as tribune of the plebs, he carried a plebiscite which indirectly secured for Caesar the dignity of pontifex maximus (Dio Cassius xxxvii.
He prohibited heathen worship at Rome; refused to wear the insignia of the pontifex maximus as unbefitting a Christian;.