Ron Johnson’s victory over Russ Feingold in 2010 was probably the highlight of that election night for me. Unlike in Illinois, the victorious Republican was a strong conservative. Unlike in Pennsylvania, the Republican defeated an entrenched incumbent and one of the most left-wing members of the Senate.

Sen. Johnson has not disappointed in office. Despite representing a purple state, Johnson has been a staunch conservative. His lifetime rating by the American Conservative Union is 93.4 percent. Similarly, the Club for Growth rates him at 90 percent lifetime.

Johnson has also been a persistent and effective critic of Hillary Clinton. It was in response to his questioning that she uttered her famous line about Benghazi: “What difference at this point does it make?”

This year, Sen. Johnson is facing the man he defeated in 2010 — ultra-liberal Russ Feingold. Keeping Feingold out of the Senate would be an important goal for conservatives even if he were facing someone less solid than Ron Johnson.

Johnson is the underdog in this race. The RCP average has Feingold nearly 8 point ahead.

However, the most recent poll, by CBS News/YouGov, suggests a much tighter race. Feingold leads in that poll by only 3 points — 45-42.

Republicans are well-organized and battle-tested in Wisconsin. If Donald Trump proves not to be too much of a drag, Johnson has a shot at defeating Feingold again. How sweet that would be!

To help make it happen you can contribute to the Johnson campaign here. I just did.