I check Rasmussen every day...and while some may argue that it favors the GOP (which is mostly wrong)...its trend line has been very stable this past couple of weeks hovering from 46-48. If there were real movement on approval, it would absolutely show up on a daily tracking poll. As it does not, this is just WaPo doing its normal push polling.
FYI...just 24% of the people polled identify as Republican. Ridiculous.