His name is Sanders, not Saunders.
Clinton is not a socialist AT ALL. She has repeatedly supported and praised the economic policies of the other Clinton presidency and has even indicated that as President she would "put Bill in charge of the economy" because of what a great job he did with it in the 90s. Bill Clinton signed into law the Republican drafted "Personal Responsibility and Work Opportunity Act" 
which essentially dismantled the New Deal, imposed 5-year lifetime limits on the receipt of welfare, prohibited people with felony drug convictions from ever receiving food stamps, and barred welfare benefits for immigrants for the first five years of their residence in the country.
Sanders' view is that inequality and economic injustice produces poverty, and that the economic system needs to be overhauled to ensure access to a decent education, health care, housing, and living wage for everyone as a baseline. The Clinton view (and I think it's equally true of either Clinton) is that the poor need to take "personal responsibility." HRC is strong on healthcare, but on the other issues of economic inequality she has a poor record of progressive positions.
She's far, far more hawkish than Sanders too. And far less strong on environmental issues.
I think that equal representation of women (in government, in society, in life) is every bit as important an issue as economic justice, world peace, and stopping climate change. I think it's entirely valid to say "I don't love everything about her policy positions, but it is long past time for a woman president so I'm voting for Hillary." I nearly said that myself in the primaries, and I will be 100% behind her in the general election.
Hillary Clinton is extremely smart, experienced, capable, and prepared for the presidency. She is many million times a better option than the GOP nightmare.
But the Democratic party has shifted ever rightward (as has the Republican party), and Bill Clinton's neoliberal presidency, with Hillary as an unofficial cabinet member and his closes advisor, represents for many hundreds of thousands of progressives the point at which their party left them and their ideals of economic justice behind. There are very good reasons why people (like me) who are desperate to see a woman president, would still vote for Bernie over Hillary, and want him to stay in as long as possible, in order to continue giving voice to the progressive base, and influence the party platform coming out of the National Convention.
If Elizabeth Warren had run, the progressives wouldn't have to choose between their desire to vote for a woman, and almost every other progressive value. I wish she had run. I bet Sanders would have bowed out very early if Warren was in the race and looked to have a chance. Sanders and Warren are ideological twins, and I hope that Hillary might choose her as running mate to consolidate the party and bring in Bernie's voters. In which case, Bernie's decision to run against Clinton in the primary and to energise the progressive base, will have been the catalyst for an all-woman ticket going into the general election.
Now that would be something to get excited about.