HARRISBURG, Pa. — Pennsylvania Sen. Bob Casey has a fine line to walk.
He and other Democrats fighting to hang on to hotly contested Senate seats have seemed jittery about the turmoil surrounding President Joe Biden after his disastrous debate performance. In many cases they're trying to minimize any damage to their own races by saying as little as possible about it in public.
But with control of the Senate on the line, the drama is an unavoidable and unwelcome development for Democrats. They are defending far more Senate seats than Republicans this year, including in the presidential swing states of Pennsylvania, Wisconsin, Michigan, Nevada and Arizona.
Incumbents in Republican-leaning Montana and Ohio appear nervous, too, and there's an unexpected challenge in the Democratic stronghold of Maryland from former Republican Gov. Larry Hogan.
The turmoil surrounding Biden is especially delicate for Casey, long seen as one of the safest Democratic bets in battleground races. He has defended Biden, but in the halls of the Capitol this week, even Casey brushed aside questions about how Biden's predicament might affect his race.
''I've got work I got to do as a senator and as a candidate," he told The Associated Press. ''I'm not going to be a pundit or an analyst. Obviously voters can make up their own minds.''
Casey grew up on the same street as Biden in Scranton. Their families have known each other for decades, and he's campaigned with Biden countless times, including this year. Biden — a Delaware resident but a Pennsylvania native, as is first lady Jill Biden — has long claimed Pennsylvania as his own.
When Casey's mother died last year, Biden came to Scranton to pay his respects.