The number Trump absolutely had to beat was 31.3 million. That was the viewership total last year for Barack Obama's final State of the Union address. It was also the smallest recorded by Nielsen since the firm began tracking State of the Union ratings in 1993.
(Note: Trump, like previous presidents, did not use the “State of the Union” label in his first year in office, but that is basically what Tuesday's speech was.)
Trump can say that he reversed a downward trend. In each of the past seven years, the State of the Union audience was smaller than in the year before. Trump, as he might say, inherited a mess.
Outdrawing Obama 2016 really wasn't be terribly impressive, however. Obama 2009 beat George W. Bush 2008, and Bush 2001 beat Bill Clinton 2000. This is hardly surprising; the first address to Congress by a new president is inherently more compelling than the last one by a president on his way out the door.
A better gauge of interest in Trump's speech is how it stacks up against first-year addresses by the previous three presidents. Clinton set the standard with an audience of 66.9 million in 1993. Trump fell far short of that number and also lagged behind Obama in 2009, though he did outdraw Bush in 2001.
Viewership for Clinton's year-one speech is the highest on record for any presidential address to Congress. If Trump wants to break the record someday, 67 million is the magic number. Here are the top 10:
It is worth noting that a large audience is not necessarily a good sign. Americans tuned in, in droves, to Bush's 2003 address because the United States was about to invade Iraq. Clinton delivered his 1998 speech in the early days of the Monica Lewinsky sex scandal. Obama spoke in the midst of an economic crisis in 2009. Bush's 2002 State of the Union was the first after 9/11.
You get the idea. Big ratings often indicate that voters are uneasy and therefore more invested than usual in what the president has to say.
With the exception of several spikes — some of which I just explained — State of the Union audiences generally decline over the course of a presidency. The long-term test for Trump will not be whether he managed to capture voters' interest Tuesday night but whether he can hold it in years to come.