It is worth noting that Denver's voting system, which is nearly identical to that of France, Louisiana and San Francisco, requires a majority vote in the first round for the leading candidate to avoid a runoff, and places the top two candidates in a runoff otherwise.
This isn't the only set of voting rules out there. In the political caucus system, all candidates with at least 30% support make it onto the primary ballot and balloting is held until at least someone gets 30%. If Denver used that rule for candidates trying to make it inot a runoff election, there would be no runoff election this year, because every race had someone who got at least 30% of the vote, and each race had only one candidate winning 30% of the vote.
Similarly, if ordinary general election voting rules were used, and the first round was a partisan political primary, a number of races, like the 8th Council District race, would be decided by now, because all the candidates were Democrats and the candidate with the most votes in the primary goes onto the next round.
But, if the city council races were partisan general election style races with primaries, the 7th Congressional District would have had a next round not between Nevitt and Watters, the two candidates with the most votes in this round, but between Nevitt and Smith, the Democrat and the Republican, respectively, even though Smith came in 4th place in terms of votes received in the first round. Of course, if there were partisan races for city council in Denver, Councilwoman Jeanne Faatz from District 2, would probably not be in office, as she is a Republican with a real shot in a nonpartisan race who would likely be defeated in a party line vote in a partisan race (most of Councilwoman Faatz's district in in Representative Labuda's state house district which Democrat Labuda easily won against her Republican opponent in a targetted race in 2006).
I like Denver's current election rules and don't think that they should be changed. But, this election is a fine example of how election results are not merely the voice of the People speaking, they are instead, a product of the rules that government them.