If you were inclined to judge, you might say something like "A politician can't mimic a Las Vegas poker table, where you 'fold a hand' and play another without risk, penalty, or moral censure." That quote, by the way, from one Doug Holyday, circa 2004.
Of course, the Deputy Mayor isn't alone in this regard - the Liberals have also fielded a sitting Councillor to represent them in this race. Neither the Liberal nor the Conservative candidate have resigned their seats; they're simply taking a "time out" to try their hand at a promotion. Nice work, if you can get it.