Trump's "foot up" on everyone.

Trump loses support among his core voting groups as the shutdown drags on, polls say...

President Trump is hemorrhaging support amid a political standoff over his proposed border wall that has resulted in the longest government shutdown on record, recent polls show.

• The president even appears to be losing favor with his core constituents.

• The poll results come as Elizabeth Warren announces her 2020 bid to challenge Trump.

• As the shutdown lumbers toward its fifth week, the president even appears to be losing favor with his core constituents, whose support for Trump until this point has been rock-solid since the 2016 campaign.

• Trump’s erosion in support has contributed to a sharp increase in the Real Clear Politics polling average of Trump's disapproval ratings.

• An NPR/PBS NewsHour/Marist poll published Thursday found that Trump's approval rating has slipped 3 percent from 39 percent, while his disapproval has climbed 4 percentage points.

• And unlike past political fights, recent surveys indicate that the groups thought to comprise key parts of Trump's base are not immune from the broader downward trend in Trump support.