Massachusetts Sen. Elizabeth Warren is seeking expert advice on how to defeat the remaining 2020 Democratic presidential nominees and, according to NBC News, she's turned to failed 2016 nominee Hillary Clinton for advice. Earlier reports indicated that Clinton, determined to re-litigate her 2016 defeat at the hands of then-New York real estate investor Donald Trump, had been reaching out to a potential 2020 candidates, offering her sage advice (though it's not entirely clear she's come to terms with precisely why she lost the contest herself). A handful of candidates reportedly took her up on her offer to chat, but Warren...