The republicans did not lose the Senate until 1986, six years after Reagan took office.
Incidentally, the effect of party control of the Senate is a better predictor of stock market performance than control of the White House or House of Representatives.
I sit corrected. Thank you.
Regardless, the rats controlled the House convincingly, and that's where "Ways and Means" happens. Also, the GOP senate included a pile of liberal, go-along-get-along Republicans at the time. Weicker, Chafee, Specter, Rudman, Stafford, Hatfield, Andrews, and Lugar just for starters. Half of the rest were squishy at best. That was one pathetic "Republican" senate. In retrospect, it's amazing Reagan got done what he did.