CNN
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The past three weeks have shaken up the race for the White House, further complicating things at the Senate level.

Democrats faced a challenging path to holding their Senate majority even before President Joe Biden’s disastrous debate performance and the assassination attempt against former President Donald Trump – and they still do. But this year’s Democratic candidates, many of them well-known incumbents, have so far been able to create some separation from the top of the ticket. The question going forward, regardless of what Biden does, is whether they can sustain it.

Nine of the top 10 seats on…