We're getting to the point in the cycle where in a lot of races the undecideds just don't matter that much because there are so few. Nevada is the best example of this. There's really no one left trying to decide whether to support Harry Reid or Sharron Angle. At this point that race is mostly going to be determined by who can persuade their voters to get out to the polls.
We have polled four close races in the last few weeks though where the undecideds really do matter and could determine who ends up winning: in the Colorado Senate race and Florida Governor race they could make a big difference for the Republicans and in the Illinois contests for both Governor and Senate they could make a big difference for the Democrats.
In Colorado and Florida both most of the undecided voters are GOP leaning. In Colorado 53% of them voted for John McCain and 38% for Barack Obama. In Florida they skew even more strongly to the Republicans- 60% voted for McCain and only 33% for Obama.
Usually you would expect those folks to end up coming home but here's another fact about those voters: they hate the GOP candidates. Buck's favorability with undecided voters is 5/42. Scott's is 3/47. So those voters are going to have to decide between their competing instincts of supporting the GOP and opposing these particular GOP candidates.
Buck trailed by 1 point on our most recent poll and Scott by 5. Their chances will improve greatly if they can find a way to convince those undecided voters to stick with the party.
We find a similar situation in reverse for the contests for Governor and Senate in Illinois. The folks who were undecided for Governor the last time we polled there had voted for Barack Obama by a 67/20 margin in 2008. Pat Quinn trailed by 7 points in our poll but if the undecided Obama voters went for him and the undecided McCain voters went for Bill Brady that would take the Brady lead all the way down to a single point. The only problem for Quinn with that scenario? His approval rating with the undecideds was 14/42. If he can get those folks to go for party over person and suck it up and vote for him he might be able to pull across the finish line.
The story in the Senate race is similar, although not quite to the same degree. There 46% of the undecideds are Democrats to only 27% who are Republicans. Giannoulias' favorability is 11/30 with them. Alexi really doesn't have too much ground to make up, at least in our polling, so if those party mates end up going with him it might just be enough to put him over the top for a small victory.
The undecideds are becoming a moot point in a lot of races but they're worth keeping an eye on in these ones.