House/Senate primaries after the conventions?

I have seen Facebook posts calling for Washington state congressmen who don’t plan to vote for Sanders at the convention, “against the will of the people of that state,” to be primaried out in August. I also notice that, while Wisconsin’s Presidential primary is in April, its House and Senate primaries are also in August - after the convention.

What other states have their House and Senate primaries in August (or later, although even early August seems to be cutting it close)? Is it even remotely possible for the Sanders campaign to use this to his advantage somehow?

Missouri’s congressional (and state office) primary is August 2. Both Clinton and Trump won their primaries by a tiny 0.2% each, so I guess some voters might be upset whichever way the state’s superdelegates – yes, Republicans have superdelegates, too! – vote.

Actually, if TheGreenPapers is correct, Missouri is one of the states where the three Republican “superdelegates” are forced to vote for a particular candidate on the first ballot - in Missouri’s case, Trump.

Ballotpedia says that WA has a filing deadline in mid May. Wisconsin has June 1. IOW, both states require you to get on the ballot fairly soon and long before the actual election. Getting on the ballot can be a long and expensive process, and (if the perception is that you’re only or mainly doing it to try to influence someone’s vote ahead of time) will be guaranteed to piss a lot of people off. Might be effective, but it’s easy to see how it could backfire.

Florida may have had their Presidential primary on March 15, but it’s August 30 for lesser offices.

On the other hand, if there’s already a challenger officially running, the convention vote might be an issue that ends up favoring that challenger.

Just to throw it out there, WA has a top two system. Primarying someone out is more difficult than it is in a state where someone’s going for the Democratic nomination.
But it seems that all it takes to file is a 1 page form and a check for $1740 or 1740 people willing to sign a petition for you, neither of which is particularly onerous if you’re seriously planning on running for Congress.