Sen. Ted Cruz, R-Texas, may be the brightest light to adorn the Republican Party in many years. He knows how to make the case for conservative ideas, pointing, for example, to the contrasting fates of Detroit and Houston to illustrate the superiority of conservative policies. So it’s particularly galling to see that rather than train his fire at President Obama and the liberal machine that cocoons him, Cruz has become a one-man wrecking ball against Republicans. His most recent foray into sabotaging his colleagues concerned the debt limit increase.

Because House Speaker John Boehner sent over a “clean” debt limit bill, Republican senators had decided to let it pass with only Democratic votes. Republicans would not be endorsing the Democrats’ spending priorities, but neither would they be opening themselves to the accusation of flirting with national default. With Obama’s political fortunes sinking and several “red state” Democratic senators in jeopardy, Republicans have a good chance to retake the Senate in November — unless they fall into civil war.