Sen. Elizabeth Warren (D-MA) took the lead in a new Des Moines Register Iowa poll on Saturday night, marking the first time the Massachusetts Senator led both former Vice President Joe Biden and Sen. Bernie Sanders (I-VT) in the first caucus state in the poll. According to the new survey, Warren narrowly leads at 22 percent, with Biden following at 20 and Sanders at 11 percent. No other candidate reached double digits but South Bend Mayor Pete Buttigieg followed at 9 percent, with Sen. Kamala Harris (D-CA) at 6 percent to round out the top five. Additionally, the poll found...