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Donald Trump is such an unusual and dangerous presidential candidate that no one should take his defeat for granted. But his defeat does look overwhelmingly likely, with Hillary Clinton leading national polls as well as swing-state polls.

The biggest uncertainty has moved to the races to determine control of the Senate and House. Here is a quick guide to the last two weeks of the campaign:

■ Thanks to recent gains, the Democrats now have a clear but vulnerable lead in the race for Senate control. Prediction markets give them a 78 percent chance of winning control, according to PredictWise.