The Democrats have hit their tipping point.

Kim Strassel reports:

"We don't look at either of these gubernatorial races . . . as something that portends a lot for our legislative efforts," insisted White House Press Secretary Robert Gibbs on Tuesday, as New Jersey and Virginia voters gave Democrats a thumping. Unfortunately for the White House, its opinion no longer counts.

On Jan. 20, Barack Obama began a race against time. The White House knew its liberal agenda would prove unpopular in many parts of the country represented by Democrats. So long as the president looked strong, those Blue Dogs and freshmen and swing-state senators would stick. Show them any sign of weakness, however, and rattled Dems would begin to care more about their own re-elections than they did their president.

Tuesday, the White House hit that tipping point.

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