General Discussion

Clinton saw both the Senate and House fall to the GOP in 1994, known as the Republican Revolution. And despite winning the election, they held in 1996.

As for the impeachment....

1998 mid-term elections
In the midst of the impeachment hearings, Clinton's approval ratings rose above 65 percent. Polls showed that many in the public did not condone Clinton's relations with Lewinsky, but they did not believe that it was grounds for removal from office. Defying predictions of congressional losses, the Democrats picked up five seats in the House of Representatives; neither party gained seats in the Senate.[140] The election represented the first time since 1934 that the party holding the presidency picked up seats in a mid-term election.[141] Gingrich resigned from office after the elections, and he was succeeded as Speaker of the House by Dennis Hastert.[140]