Yes, it happened all the time, but not as you've described. It was exceedingly rare for a candidate to hold the same office twice, except with the consulship where it was actually not at all uncommon, or at least not nearly so rare as a lot of people seem to think. There are only a handful of non-consular repeats. Ti. Gracchus ran for the tribunate twice in a row, and was killed on voting day. C. held the tribunate in succession and A. Saturninus held it in 103 and 100 and was elected for a third tribunate for 99 but was killed days before assuming it. That's the last repeat tribunate of the Republic, although there might be some under the emperors. The Catilinarian conspirator P. Lentulus had been praetor 74 and cos. 71 but was expelled from the senate by the censors of 70. By the time of his execution in 63 he was a sitting praetor. According to Sallust he had climbed his way back up, but it isn't known whether he had had to attain the quaestorship a second time or whether he went straight to a second praetorship. That's the only repeat praetorship I can think of, although there may be one or two others. I'd have to look up whether there were any repeat quaestorships or aedileships, but it would take a while and I have reasons to doubt it very strongly.

The reason why I doubt it is that it doesn't conform with the nature of elected magistracy. The Roman aristocracy was extremely competitive, and its status was very much dependent on that competition culture. Between themselves Roman statesmen competed over the honor of offices--that's what political office is usually called in Latin, "honos" or "honor"--which in Roman political thought were granted to remarkable individuals who deserved them by the generosity of the people. This was a particularly important point in Roman political thought, that the people both granted and took away magistracies as a reward or a punishment for the good or bad actions of individual men, whose desserts were judged by various standards including their ancestry and just innate quality of character but also by their deeds and actions in the interests and defense of the people. This latter is how novi homines tended to be elected, and in the Jugurtha Sallust explicitly has Marius following his assignment as consul to the Jugurthine War point out that his actions in increasing the imperial power of the Roman people place him as more deserving for command than the people who have been appointed before him.

The cursus honorum, then, was quite literally a "cursus," a race or a path going in one direction. For a very brief period tribunates were held in succession but that was because the tribunate's position as part of the cursus was for a while unclear and because of the unusual quality of the tribunate, a tension which soon took different forms after Saturninus or, at the latest, the Social War. Other than that brief period when repeat tribunates were considered valuable there was simply no value in holding a repeat magistracy. It's an oft-repeated falsehood that repeat magistracies were forbidden, or were restricted to a period of one tenure every few (ten) years. Even classicists and ancient historians say that sometimes, but there's simply no evidence for it, and the evidence clearly indicates that it's not true. The whole point of magistracy, as far as the competitive aristocratic culture was concerned, was to hold ever-higher offices. No additional reputation was accrued from holding the quaestorship multiple times, and given the enormous effort involved in managing a candidacy there was no reason to try for a lower magistracy again once it had been held once.

This is not to say that Roman aristocrats did not value their elected magistracies for ideological reasons. This seems very much not to be the case. We have lots of reports of people who performed their duties as magistrates attentively, and it was a mark of particular pride for a magistrate to leave office and be able to say that he had done his job remarkably well. Furthermore, that relationship between the people rewarding magistrates and magistrates living up to the honor that they had been granted weighed heavily on the minds of Roman candidates and magistrates. Morstein-Marx has shown how both Sulla and Cinna appealed to the idea that they had been unfairly robbed of their people-granted commands without the decision of the people when they rallied forces to storm the city in 88 and 87. Elected magistracy was a bill of command, and while magistrates often had an enormous amount of power and very little oversight in "constitutional" terms, Roman statesmen did not often think in a way that we would call constitutional, and by and large tried to fulfill their duty to the people who had rewarded them with honor.

The honor of magistracy was not merely abstract, it was quite practical. There were only so many magistracies to go around, and after Sulla things became even more competitive. Sulla's law of the twenty quaestors increased the number of quaestors to...twenty, and for a brief period between Caesar and Augustus there were 40 (supposedly...Dio is our only source for this). It's debated why the number of quaestors was increased, although at least one effect was that it could help with senate attrition. In any case, Sulla also increased the praetors to 8 (there were 10 under Caesar). This all looks rather academic, and on paper it looks like there are more available positions to receive the honor of magistracy. But if you consider the entire cursus as a whole--which is what a Roman candidate would've done, looking towards the next step before he had even reached the current one, all the way up to the consulship--the picture is quite different. Sulla doubled the number of quaestors. This means that each year there are twice as many young men entering senatorial careers. Every single one of these young men is hoping to reach the consulship. But the number of praetors was not doubled under Sulla. Only two were added from the previous number of 6. Which means that more young men are failing to reach even the praetorship. And then of course the consulship is still just two dudes. Your chances of reaching even a praetorship, competing in your own age group, is no better than 40%. Add in candidates from the two years above yours that didn't make it the first time and are trying again and your chances diminish substantially. Your chances of reaching the consulship competing only against your age group are only 10%, and adding in candidates who failed their first year or two at the consulship and you're in the single digits.

It's no wonder, then, that so few praetors even tried for the consulship. In a highly competitive consular election there might be four to five candidates. In a more normal cycle there were typically only three. The praetorship was a bottleneck, and even reaching it required a fair amount of work and luck. Lots of Romans from notable families never made it to the consulship or even the praetorship. More than a few of them are even well known. The younger Cato, for example, only made it to the praetorship in 54, and when he tried for the consulship he lost. Cicero's brother Q., despite being a year or two older than Caesar, was Caesar's praetorian colleague in 62. He would've been eligible for the consulship probably as early as 59, when Caesar held it with Bibulus, but he never held the consulship and to our knowledge never ran (although he may have been planning a candidacy in 51 when he left Caesar's army to return to Rome), despite being the brother of no less than M. Cicero himself. Most praetors clearly didn't feel confident enough in their ability to swing voters to try for a consular bid. Failure could be a worse stain on your reputation than just not trying, depending on the circumstances.

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