In the exhibit hall of the Washington Hilton this week, Take Back America conference participants cast IRV ballots in a straw poll for the 2008 Democratic presidential nominee. They chose Al Gore over Russ Feingold 51 to 49 percent.

Under IRV, or instant runoff voting, voters rank their candidates in order of preference - 1 for their favorite, 2 for their second favorite, and so on. The winner must have a majority. If no candidate has a majority of first choices, an instant runoff kicks in. The candidate with fewest first choices is eliminated, and those ballots count toward the respective voters' second choices.

Feingold led the first round with one more first choice than Gore. Barack Obama was a handful of first choices behind. By the 9th round, Feingold led Gore, with Obama behind both. But in the tenth round, voters who had supported Obama broke in favor of Gore, making him the winner.

Under traditional primary rules, Feingold would have won with a narrow plurality of 22%. Obama would have been a spoiler candidate - and a focal point for the opprobrium of many Democrats.

91% of ballots factored into the count in the tenth decisive round, telling us there was relatively little undervoting (or non-use of one's full voting strength). It also suggests there were relatively few wasted votes (or votes that do not help elect a candidate). Indeed 51% of votes were effective. By contrast, under traditional primary rules, 79% of votes would have been wasted. This was a very fractured electorate - as 10 rounds of counting indicates - but IRV still picked a majority winner with minimal wasted votes.

2.4% of voters cast invalid ballots - not at all shabby given there had been zero voter education. Voters also were distracted by our pitching reforms to them, activity at other tables and simultaneous conversations with other participants.

FairVote has run IRV straw polls at Take Back America for the last three years. You can see results and analysis for 2004 and 2005.

We're interested in your own analysis of the results, which you can download here in Excel format. Assuming the three poll leaders - Gore, Feingold and Obama - don't run, who will pick up the support of progressive Dems? Without Feingold in the race, what would have happened to Gore? To lower ranked candidates?

Notes on counting rules

1) When candidates tied for elimination, we eliminated the one with the least core support - or fewest first choices.

2) We eliminated McCain, Brown and Vilsack - with one first choice each - together in the first round.