Rand Paul May Save Republicans. Ted Cruz May Kill Them.

If Paul is working to stretch the party's narrow boundaries -- on race, youth, the environment, national security -- Texas Senator Ted Cruz is driving Republicans ever deeper into their ideological cul-de-sac.

I doubt Rand Paul will ever be president. But he might rescue the Republican Party, which would still be a pretty good line on his resume.

Paul is suddenly getting good press. Rich Lowry, editor of the National Review and not a natural adherent to Pauline philosophy, was positive in Politico. Both the New Republic and the Washington Post have run largely flattering profiles, with the formerdeclaring, "He's becoming a better politician every day."

He's already pretty good. In recent weeks Paul has shown impressive elasticity, appearing before Iowa conservatives -- a virulent strain -- at the Lincoln Day Dinner in Cedar Rapids and a roomful of black students at Howard University. The Howard visit, along with another appearance at traditionally black Simmons College, won't make Paul's demographic wish come true (he told Fox News host Sean Hannity that he wants Republicans to reap 20 percent of the black vote, up from wobbly single digits), but it clearly distinguishes him in a party steadily poisoning itself with racial exclusivity.

After conducting a one-man filibuster against free-range drones, Paul was perfectly positioned to dominate the story of National Security Agency leaks. And he has, in part because he appears genuinely disturbed by government surveillance and is one of the few articulate politicians who isn't ambivalent about the NSA's long tentacles. As Lowry wrote in Politico, "This is the kind of issue Rand Paul was born and (literally) raised to raise holy hell over."

Arguably as important, if less tangible, is Paul's "crunchy con" persona. At a Reagan library event, he extolled the virtues of composting. This is anything but trivial. Conservatism in recent years has defined itself largely by what it hates: Obama, liberals, government. Environmentalism is high on that list, as a toxic stream of votes in the House of Representatives confirms. Paul's embrace of composting is brilliant: It suggests a thoughtfulness about the environment (along with an absence of hatred) without in any way challenging Republican petro-donors.

Paul's fiscal policy, including a flat tax and a grim reaper approach to federal departments and the federal budget, should be enough to keep him penned in on Congress's end of Pennsylvania Avenue. But a Paul presidential run might begin to liberate his party from other orthodoxies.

If Paul is working to stretch the party's narrow boundaries -- on race, youth, the environment, national security -- Texas Senator Ted Cruz is driving Republicans ever deeper into their ideological cul-de-sac. Cruz has had a glittering career: Harvard Law Review, Supreme Court clerk, Texas Solicitor General. His resume is filled with "first" and "youngest," and the general thrust is pretty clearly "best."

Cruz's high IQ, however, is betrayed by his politics, which are comparable to those of the dimmest goobers on Capitol Hill. IRS in the news? Cruz gliblycalls for abolishing it. Nominee for defense secretary? Cruz slanders him so crudely that he earns a rebuke from Senator John McCain and a comparison to Joe McCarthy -- from mild-mannered David Brooks, of all people.

Rather than using his Cuban roots to help the party navigate the shoals of immigration reform, as Florida Senator Marco Rubio is doing, Cruz has taken the easy, destructive route, spewing demagogy and backing poison-pill amendments. When House majority leader Eric Cantor tried to get Republicans on record supporting something, anything to suggest the party's health-care agenda is more than a homicidal rage against Obamacare, Cruz's aides worked to torpedo it. The bill's failure in the House was a political fiasco.

Somewhere between Paul's calculated stretch and Cruz's cynical contraction, is a third freshman, Rubio. He has been drifting between those two shores, never quite reaching the far ends of either. If Rubio survives the ordeal of immigration reform, Paul's efforts to broaden the party would eventually aid a Rubio presidential campaign in 2016. Cruz's ugly tactics, on the other hand, show a sure road to destruction. Freshman-wise, it's not much of a contest.

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