I dislike political arguments that ignore other options. One of them is the argument for granting statehood to the District of Columbia.
The simplest way to re-enfranchise citizens of the District of Columbia is not the creation of a new state. Since that would violate the constitutional requirement that the federal government be separate from the states, it would require a constitutional amendment, which is not an easy process.
The second option is to shrink the District of Columbia to an area that only contains the Capitol, Supreme Court, and White House. The only disenfranchised citizens are now the president and his family, and I think being the Executive branch is an adequate means of having your political voice heard.
But (as I've written before, actually), the SIMPLEST simplest way of fixing this problem is repealing the Organic Act of 1801 which disenfranchised District citizens who previously had been represented by Virginia and Maryland elected officials.
Modern government is like the man who tells his wife the wonky leg of the dining room table can only be repaired if he purchases a new lathe and a laser-guided drill, which--yeah--that's a lot of money, but otherwise the table will never be fixed and it's possible it would collapse during dinner and KILL little Johnny, and why does his wife want little Johnny to die? There's no one saying, "What if we ate at the kitchen table instead?" Or, more aptly, "Why don't you stop making the table leg wonky?"