investigation. they're going for a jackpot by trying to get the testimony of john bolton, the national security adviser. we're told that he will not show up voluntarily, he'll need a subpoena or a court. but, here's the why it matters. if he's compelled to testify, look out. john bolton knows a lot. we're told by someone very close to him he want be demur, won't hold back. the trump campaign, on the other hand, is focusing on swing states they need to shore up. so they say that after this impeachment vote they're going to have a data-driven effort in key states to go after members who are in tough districts to take a vote on impeachment and they point to polls in these swing states showing that for now the president's support is holding up. >> mike, we mentioned a bit earlier that twitter announced it's going to ban all political advertising. give us the axios take on that. >> there's a great tweet on this that said this was the best