They based that conclusion, in part, on another finding — which they say was also reached with high confidence — that the Russians hacked the Republican National Committee’s computer systems in addition to their attacks on Democratic organizations, but did not release whatever information they gleaned from the Republican networks.How does that evidence support the finding that the Russians were trying to help Trump and hurt Hillary — as opposed to just hacking into everything they could? Are senior Obama administration officials reliable in making that leap or is this political junk?
There's also the evidence that "it was largely documents from Democratic Party systems that were leaked to the public" (through Wikileaks). You have to interpret that evidence. Republicans say "their networks were not compromised, asserting that only the accounts of individual Republicans were attacked." The NYT cites a "senior government official" corroborating that position.
The NYT also raises the theory that the Russians — like most people — assumed Hillary was going to win, and they weren't trying to defeat her, but undercut her presidency. In this theory, they weren't so concerned with hurting Trump because they didn't think he'd win.
I'm reading these new conclusions as political junk.