Where do you get the assumption that those filing to run don't live in the district? Isn't that a requirement to run for the House?
No. The Constitution only requires that a prospective House member be an "Inhabitant of" the state he represents "when elected". He or she need not live in the district he or she represents. In theory, he or she doesn't even need to live in the state until election day.
True. Former Congressman Rod Blagojevich lived in Chicago, IL, but did not live in the congressional district that he was elected to represent (the 1996, 1998, and 2000 elections -- then he ran for Governor in 2002). Current congressman Bob Brady of Philadelphia, PA, did not live in the district he was elected from the first few times he was elected to the House (special mid-term election in 1998, then the general election so if 1998 and 2000), although when the state drew new district lines in 2001, at that point the legislature deliberately placed his home within the new boundaries of his district.
The constitutional interpretation which results in the "rule" that anyone who resides in this or that state can get elected to represent any district within the state, even though they do not live in the particular district they were going to represent, was rendered by the U.S. House itself over 200 years ago, in the early 19th Century. Maryland adopted a law that everyone who will represent their state in the U.S. House has to live in the congressional district that they were going to represent, but the House decided to ignore the state law and seat someone who did not meat that state's requirement. Simply put, the U.S. House decided the state law of Maryland was unconstitutional. The U.S. Supreme Court has upheld that interpretation as well.
On another note, I agree with a previous poster that the OP has a poorly-written headline. The fact that Democrats have been inspired to run for Congress because of their reaction to Trump's presidency is no reason to attribute a "push" to Trump himself.
