Several Democratic senators reportedly plan to introduce as soon as Thursday a set of principles and legislation aimed at fixing parts of ObamaCare amid concerns the law could cost Democrats House seats and possibly the Senate in November. Sens. Mark Warner, D-Va.; Mark Begich, D-Alaska; Mary Landrieu, D-La.; Heidi Heitkamp, D-N.D.; Joe Manchin, D-W.Va.; and Sen. Angus King, I., Maine, will introduce proposals to improve the law, The Wall Street Journal reported. Begich and Warner have called for allowing "copper" plans on the government-run health exchanges. The new insurance plans would offer lower premiums and higher out-of-pocket costs than the...