A senior Obama campaign official said while there’s some concern about the amount of money being raised on the Republican side, especially by outside groups — including Karl Rove’s American Crossroads super-PAC — “it’s only natural that less than four months before an election … things are going to pick up dramatically for both sides.

“It’s July, and the election is in November,” the official said, comparing Obama’s new schedule to those of previous incumbent presidents Bill Clinton and George W. Bush. “This is crunch time right now, because this is when people are tuning in.”…

“There’s a very real sense of, ‘You can’t just sit back,’ ” the former official said. “There’s so much money on the other side, and we’re in unknown waters. If people are freaked out, I think they should be freaked out. After all, it’s the new reality of American electoral politics. And we’re venturing into the great unknown.”

Don Peebles, who serves on Obama’s National Finance Committee, told The Hill he’s “concerned [Obama] won’t have sufficient resources to fight back with.”