It's great that Hillary won Nevada, she needed it. As for South Carolina, if Rubio does end up winning the nomination somehow, Democrats will need to really show how far right the guy is; he's no moderate.
If you're gonna bring up invading Iraq, keep in mind Hillary was all for it, voted to extend the Patriot Act, thinks Edward Snowden's a traitor, and wants to intervene in Syria while enacting a no fly zone.
When it comes to military philosophies, Hillary's very hawkish.
What Hillary voted for was a 'maybe use force if negotiations break down' bill; it was not a 'war on Iraq' bill. She wrongly believe Bush's lies that he's only attack if necessary, if negotiations failed and the search for WMDs was stopped. Of course, he was lying, and went to war anyway. I saw that coming and thought that Hillary and the other Democrats voting for it were making a big mistake, but she believed him, unfortunately, and has since said that she was lied to and the vote was a mistake. That's not as good as opposing it from the start, but is much better than nothing.
But importantly, basically, there is no way that the Iraq War would ever have happened under a Democratic administration. That war only happened because the Bush Administration was determined to attack Iraq to make up for Bush I not taking out Saddam, for oil, etc. No Democrat would have done what Bush did, with the lies about Saddam's (nonexistent) connections to 9/11, the lies about WMDs, etc., all designed to get support for an unnecessary war. With the full intelligence picture that only the Executive Branch had, anyone not determined to start a war there would have known that there was not reason for it. And only Bush, Cheney, Rumsfeld, and co. were so determined. Hillary and other Democrats certainly were not. Even if she voted for a bill that resulted in the war happening, she'd never have started that war herself, and I do think that matters.
Further, if you watch the debates, Bernie is no pacifist; on foreign policy, Bernie and Hillary agree on almost everything -- the main disagreements on our foreign policy issues today are issues like 'what tone should we have with Iran' and the like. Watching the debates, their near-total agreement on foreign policy is striking. Bernie has to constantly bring up that he voted against Iraq because it's one of the only things that separates them on foreign policy -- he voted for most all the other military actions that she also supported, in Kosovo, Libya, etc. Bernie wants to cut the military budget more than Hillary, yes, but he's not a full-on pacifist.
On the Patriot Act and Edward Snowden, though, yes, I would say that she's on the wrong side of those issues. On Syria, I'd probably agree with her that we need to do more.
Gerrymandering doesn't apply to the Senate.
Well, no, but the Senate has a built-in Republican bias since there are more right-leaning states than there are left-leaning ones. More of the left-leaning states have larger populations, which matters for the House and the Electoral College, but not for the Senate. If all states voted with their current partisan alignments, the Senate would be Republican and would probably stay that way for a long time.