Beyond Gerrymandering Prevention

Even if you have independent commissions trying to be fair in how they draw districts, any given set of districts can be systemically biased in favor of one party or another. To get beyond that, a bigger reform is needed.

One such reform, which would make sense to introduce as a proposed constitutional amendment by initiative, at the state legislative election level, probably at first, only for the state house where every member faces the voters every two years, would be mixed member proportional representation.

This is or was used in New Zealand for its parliamentary elections.

In this system, Colorado would hold state house elections in 65 seats just as it does now (although with either ranked choice voting, or a runoff election between the top two candidates if no one wins a majority to eliminate third-party spoiler effects).

But, once the election was over, you would tally up the percentage of the popular vote cast for state house candidates from each party that won at least one seat in the state house.

Suppose that Democrats won 53% of the popular vote, Republicans won 42% of the popular vote, and third-parties won 5% of the popular vote, but the Democrats got 32 seats, the Republicans got 33 seats and third-parties won no seats in individual districts, due to gerrymandering. The Democrats would get 10 bonus seats to reconcile the popular vote to the per district total, and the state house would be expanded to 75 seats, 42 held by Democrats and 33 held by Republicans.

In addition to leveling the scales and encouraging voter turnout in "safe" seat races, it would also eliminate the incentive to gerrymander in the first place. But, the lion's share of the legislators would still be elected from traditional single member geographically based constituencies, providing a level of familiarity about their role.

Another reform which would also be adopted by initiative would be to elect the state senate by a party list system of proportional representation. Each voter would choose a political party rather than a candidate in the state senate race, and the seats would be allocated the political parties based upon their percentage of the vote, with a minimum threshold of about 1.5% to get at least one seat. 

In that scenario, suppose that Democrats won 53% of the popular vote, Republicans won 42% of the popular vote, and a third party won 5% of the popular vote. The third-party would get 2 state senate seats, the Republicans would get 15 state senate seats, and the Democrats would get 18 state senate seats.