The data is here: https://d25d2506sfb94s.cloudfront.net/cumulus_uploads/document/q8r0rkibs1/econTabReport.pdf
Since this is one poll you can't use these results as exact percentages of all Trump supporters but you can learn some things about the typical or average Trump supporter.
The Media
72% of polled Trump supporters (remember there is going to be some variability in this number) think the media is done a "worse than usual job" covering this election than previous elections. A 95% confidence interval would be (67.6%,76.4%) so we could safely say it is very likely that most Trump supporters do not think the media is doing a good job with this election.For comparison 50% of Clinton supporters (and 58% overall) think the media has done a "worse than usual job")
The Government
6% of polled Trump supporters "Strongly approve" or "Somewhat approve" of Congress's job performance (the percentage for all responses was 13%, and 12% of republicans). 18% of polled Trump supporters were neutral.
A 95% confidence interval would be ( 3.8%,8.22%) for "strongly approve" or "somewhat approve" of the performance of congress.
95% of polled Trump supporters say the country is on the wrong track.
For comparison this number was 65% overall.
The top 4 most important issue (listed in order) of the Trump supporter in this poll are: Terrorism, Social Security, Immigration, The economy.
For comparison for all respondents the four top issues were : Social Security, the economy, Terrorism, Health Care. For polled Clinton supporters they were : Social Security, the economy, health care, the environment/gun control (these were tied).
Conclusion
The typical Donald Trump supporter doesn't like the media coverage of the election, direction of this country, and Congress, more so than other people. Because of this they may not care about endorsements as much as the usual voter. Another interesting thing is that 51% of polled Trump supporters said they felt enthusiastic about Donald Trump, but only 38% of polled Clinton supporters felt enthusiastic about Hillary Clinton. Since this is one poll from a few days it's not going to give us the answers to the opinions of all Trump supporters but it can help to explain Trump's consistent support regardless of his actions. These opinions may also explain why Trump won the primary with very few endorsements from politicians (compared to previous years). Trump's supporters (especially those who have been with him since the primary) are not going to change their mind at this point.