The second portion of that headline is a non-starter; Clinton had a big lead in the polls over Sanders going into the debate and there seems to have been no change in their relative positions afterward. As for Clinton's being judged "winner of debate" that depends very much on who is doing the judging and what the criteria are.
My impression regarding Clinton's performance was that much of what she said in this first debate was a response to the Sanders challenge. Bernie has moved the discussion off center to the left, and Hillary is adopting talking points that appeal to that portion of the electorate that Sanders has invigorated.
The questions that must be asked are: does Clinton really believe in the issues she now seems to be championing and even if she does, what are the chances that the positions she are advocating will result in major changes if she takes the presidency?
Clinton's statements about gun control are usefully illustrative. A clear objective in this instance was to undercut Sanders by adopting a stance on the issue to his left. In the short run, she probably did gain some ground in regard to the primary election. What about the general election? Would her position on gun control evolve? And, if she gets in office, what are the chances that she will lead the way to substantial changes in regard to gun violence?
In my opinion, Clinton did nothing in the debate to bolster her credibility or to change the perception that she would be unlikely to rock the establishment's boat if elected. She certainly did not advance seriously strong support for getting big money out of the election process.
Bernie Sanders, in contrast, clearly believes in the positions he has advocated over a lifetime in politics. He brought those convictions to a national stage in the debate and he forced the Democratic establishment and the country to confront the real issues of election financing reform, rising economic inequality, inadequate health care, diminishing educational opportunity, and endless wars.