Republicans will need a net gain of only two seats to retake the U.S. Senate in November. Democratic strategists know they are likely to lose the U.S. Senate seat presently held by West Virginia centrist Sen. Joe Manchin, who isn’t seeking reelection. In that race, Republican Jim Justice is way ahead of Democrat Glenn Elliott — which makes it all the more important for Democrats to maintain the seats they are defending in Montana, Ohio and other states. But according to The Hill’s Alexander Bolton, some Republican strategists fear that GOP presidential nominee Donald Trump “could be blowing th…