As one succinctly explained:
Today is your last chance to chip in before the critical FEC filing deadline at midnight tonight.I'm not going to name names, or encourage your support for any particular Democrat, but the filing deadline is important. When the numbers come out, they play a large role in framing which races are hot and which aren't, and which candidates are legit and which aren't. When Democratic incumbents show big numbers, it helps scare away challengers. When Democratic challengers running for GOP-held or open seats show big numbers, it makes those Republican incumbents sweat, and it draws attention from Democratic committees and PACs, which are looking to help potential winners.
Let me be clear: I hate the role that money plays in our electoral system. I want serious campaign finance reform. But until that happens, this is how the game is played, and Democrats have to try to keep up. If you've been thinking about donating to a favorite candidate, this would be a good day to do it.