Pareene Kornacki bets that Ted Cruz will hold back the GOP:

Cruz is now positioned as a major obstacle to the ideological modernization that the Republican Party is desperately in need of. If his brand of conservatism is treated as the gold standard of purity by the conservative media and conservative activists, Republican leaders will have a hard time moving the party away from its Obama-era orthodoxy. This could affect the calculations of Republican office-holders in the coming months, as Congress tackles immigration, guns and other issues on which the GOP is out of step with mainstream opinion.

Waldman’s take on the controversial new Senator:

A year or two ago, if you asked Republicans to list their next generation of stars Ted Cruz’s name would inevitably have come up. Young (he’s only 42), Latino (his father emigrated from Cuba), smart (Princeton, Harvard Law) and articulate (he was a champion debater), he looked like someone with an unlimited future. But then he got to Washington and started acting like the reincarnation of Joe McCarthy, and now, barely a month into his Senate career, we can say with a fair degree of certainty that Ted Cruz is not going to be the national superstar many predicted he’d be. If things go well, he might be the next Jim DeMint—the hard-line leader of the extremist Republicans in the Senate, someone who helps the Tea Party and aids some right-wing candidates win primaries over more mainstream Republicans. But I’m guessing that like DeMint, he won’t ever write a single piece of meaningful legislation and he’ll give the Republican party nothing but headaches as it struggles to look less like a party of haters and nutballs.