Enacting meaningful election reform is going to be an uphill battle. But perhaps there's an easier way to get a foot in the door. Currently, the national Republican party is reconsidering the rules for its presidential primaries. The plan coming from the national party would require that the states--at least those earliest in the primary season--divide their delegates in some proportion based on the percentage of votes each candidate receives in the primary, rather than using a winner-takes-all approach.
Presumably, this is coming as a response to John McCain's "win" in the Florida primary, way back in January of 2007 (seems like forever ago, doesn't it?), where he got 36% of the votes, but 100% of the delegates. Allegedly, this led to McCain's nomination, despite most Republicans wanting someone else. (The first post to LoAE was about this very issue. Oh my, I was still planing to advocate for Condorcet methods then!)
This will be a difficult process to implement. While there could be some potential improvement in national outcomes if every state delegation went with a proportional division, this is in opposition to the fact that each individual state can improve it's own power by sticking with winner-takes-all. It's the same reason that only a couple states divide their electoral college votes: by dividing your effort, you weaken the effect you have on the outcome. It may be possible for the national party to convince the state parties to give up this power, but someone, somewhere, is going to lose out in this transition.
But let's take a step back: the deeper problem here is that the national Republican party is trying to find a better way to make plurality votes decide an outcome among more than two possible choices. Whether or not to divide delegates up is missing the forest for the trees; the problem is that plurality voting sucks when there are more than two options.
The answer (which you've already guessed if this isn't your first time here) is approval voting (or score voting). Under approval, rather than have each voter vote for one, and then divvy those up somehow among several delegates who will also each vote for one, a better result can be obtained by having each voter approve of as many candidates as they want, and then assign a proportional number of delegates to submit approval for those candidates, potentially even having some delegates approve of multiple candidates. If 55% of the voters approve of A, have 55% of the delegates approve of A; if 65% also approve of B, have 65% approve of B, even if that means that (at least) 20% will have to approve of both. A similar procedure can work with score voting; if a candidate's average score is 5.5/10, have 55% of the delegates approve of A, and so on.
This process will require a larger change than perhaps the party can manage (it will require changes in all states, not just a Florida and a few others), but it will lead to much better results than any proportional-division plan based on plurality ballots could.
In the larger sense, entering the political system via party primaries is potentially a much better way to get approval (or score) voting adopted: while in the general elections, alternative voting methods could only hurt major parties (to the benefit of third parties), in a primary election it could only help, by delivering better candidates into the general election whenever more than two candidates vie for the nomination (where "better" is determined by whatever the voters think it means).