Nate Silver lays out a four-point plan for McCain:

1. Give-Ups. McCain should concede Pennsylvania, Wisconsin, Minnesota and Iowa.

2. Offensive Targets. McCain should remain engaged in New Hampshire and New Mexico.

3. Defensive Targets. Some reasonably vigorous defense is required in Viginia, Colorado, Nevada, Ohio and North Carolina.

4. Gambles. McCain should limit his activity in Florida, Missouri and Indiana, and hope a national surge of some kind brings those states back into his column.

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