She wouldn't drop out. It wouldn't have much effect on the race.
LOLOLOLOLOLOL. An indictment by the FBI could go one of two ways.
1: Clinton receives a subpoena - Obviously a terrible situation. For now, Clinton's lack of honesty can only hurt her so much, as people who actually want a democrat to win the general may want more reason than a collection of focus-group-tested flip-flops to back a literal socialist who is perceived as unelectable. However, with Clinton actually being called into court, not only would her honesty ratings plummet even more, she'd now have a YUGE "CRIMINAL!" sticker on her back. Reid can squeal about "innocent until proven guilty" all he wants, but recent history shows that the electorate doesn't really think that way. Indictment (especially with a full subpoena) equals politically dead, at least for the cycle, unless your name is Michael Grimm. Just ask the ghost of Ted Stevens, John Walsh, or Ed Fitzgerald (yes, I know the last one isn't a perfect fit, but still). Assuming the courts didn't force Clinton out of the race, her polls would plummet and plummet fast.
2: Obama pardons Clinton: Obviously Clinton can stay in, but it would still act as a lesser version of 1: and she would drop significantly in the polls. However, if she can successfully cast the FBI as a partisan organization (far easier said than done), it's possible she could still slip through, though I imagine there would be pressure for her to drop out and let O'Malley try instead.
