Thinking about it a bit more, impeachment probably isn't the answer right now. All we have is the word of s convicted felon.
However, there most certainly is smoke here, WRT the Trump campaigns finances. What we really need is a new Special Councel to dig into the campaigns finances, and especially it's principal contributors...including (but not limited to) the Trump family and the Trump Org.
This Councel is not charged to look into Russia but any and all financial crimes stemming from the campaign and any other financial crimes uncovered during the course of the investigation.
Or, maybe Mueller is on it anyways and will issue a wholly independant briefing to DoJ/Congress when he's done. Either way.