Big Trend towards Democrats among Likely Voters

For those struggling to make sense of the avalanche of polls this week, this result from the Cook Political Report/RT Strategies Poll could be of enormous significance.

Cong. Generic Ballot (RV): Dem 52 Rep 39
Cong. Generic Ballot (MLV): Dem 61 Rep 35
(RV = registered voters, MLV = most likely voters)

The generic congressional question has been trending in the Democrats' favor for some time now. But when the survey screens for likely voters, the numbers shift 13 points further to the Democratic column. If this result is accurate, it means that those inclined to vote Democratic are significantly more likely to go to the polls than are those inclined to vote Republican.
This result is not an outlier, but reflects a trend that has been growing since September. Responses to questions about how likely one is to vote generally are more meaningful as Election Day approaches.
I don't think this result is predictive of turnout in Delaware, since we don't have a close race for Congress. But if this result does foreshadow turnout across the country, then it could be a big night for Democrats.