Seven Republican senators now are calling for their leadership elections to be delayed — with one even promising to walk out rather than vote Tuesday.Why it matters: Senate Majority Leader John Thune (R-S.D.) is still expected to be reelected to lead the Senate GOP tomorrow. But the growing push to delay is a sign of troubles ahead.Driving the news: Sens. Ron Johnson (R-Wisc.), Rick Scott (R-Fla.), Mike Lee (R-Utah), Ted Budd (R-N.C.) and John Kennedy (R-La.)