Trump's base probably isn't going anywhere post-shutdown

(CNN)When President Donald Trump reopened the government (temporarily) without any funding for his wall, the move hurt his image among some conservative commentators and Trump backers who accused him of being weak and caving to House Speaker Nancy Pelosi.

But it's unlikely that those Americans who approve of the job he's doing will actually see him any differently as a result. Republican approval of the President has been relatively stable since he stepped into office.
According to CNN's most recent polling, conducted in January during the partial shutdown, 81% of Republicans approve of the job Trump is doing as president and 16% disapprove. While 81% is on the low end for approval of Trump's approval among Republicans, it's around the same as President Barack Obama's two years in to his first term (84% approval among Democrats).
Trump's highest approval within his own party was 90% immediately following his inauguration in 2017. His second highest approval among Republicans was in November, 2018 (at 89% approval among Republicans), before the midterm elections, when control of Congress was up in the air but Trump's face was everywhere, campaigning all over the country for 2018 candidates.
    During his two years as president, Donald Trump's approval among Republicans has only fluctuated 10 percentage points in CNN polling. That's unprecedented compared to past presidents and backed up by other polling.
    Gallup polling has Trump with a slightly different approval than CNN, 88% among Republicans in their mid-January poll. But the gap between Trump's highest and lowest approval over his entire presidency is the same as the gap in CNN's -- 10 percentage points.
    According to historic Gallup polling, the average gap between a modern president's highest approval rating and their lowest among members of their own party during their first two years in office is much greater, around 23 points. This includes US presidents (except Trump) since Jimmy Carter.
    Carter is actually the modern president with the largest approval gap among Americans of his own party. He enjoyed a high of 84% approval among Democrats in March 1977 and suffered a low of 34% in October 1979, during the 1979 oil crisis in the wake of the Iranian revolution. That low mark in 1979 wasn't within his first two years so it is not perfectly comparable to Trump's very steady numbers. Carter's low during the first half of his time in office came when he hit 49% among Democrats -- still a 35-point gap.
    President George W. Bush is an exception since his approval rating varied so significantly due to an extremely high approval from both parties he enjoyed after the 9/11 terror attacks. His swing among Republicans was only 14 percentage points in his first two years. That's still more than Trump's, but not by much. However, during his entire presidency, Bush fell greatly among Republicans and the high-low swing among Republicans for his entire four years was 44 percentage points. He hit just 55% approval among Republicans in October of 2008, just before the election of Barack Obama.
    Bush's father, President George H.W. Bush and President Reagan both saw gaps in their approval of 26 and 25 points, respectively.
    President Barack Obama had a 93% approval among Democrats in May 2009 when he hit 100 days as president and saw a low of 76% in August, 2010, just before Democrats lost control of the House of Representatives. That's a 17-point gap in his first two years. And it's not much different -- a 21-point gap -- for his entire presidency.
      Even among all Americans, not just Republicans, Trump's approval is relatively steady, with a gap of 10 points in Gallup's polling.
      If you average other presidents entire tenure, the gap between their highest approval in their own party and their lowest are even larger, with an average of 36 points, including Bush's 44-point drop in approval among Republicans