A round up of Specter related commentary from across the ideological spectrum, courtesy of RCP's David Russell:

Specter Had Disavowed Switch – Eric Zimmerman, The Hill

Specter's Second Party Switch – Mark Silva, The Swamp

Not All Democrats Supporting Specter -  Josh Kraushaar, Politico

Specter Playing for Both Teams - Ryan Sager, TrueSlant

What Does the Supermajority Mean? – Marc Ambinder, The Atlantic

Specter Opts to Survive – Dick Polman, Philly Inquirer

Toomey Shrinks the GOP – Alex Knepper, Race42008

Why Specter Had to Switch – Eric Kleefeld, TPM

The Democrat Most Deserving of a Primary Challenge – Chris Bowers, Open Left

Guess Toomey Has the GOP Primary Won – Jim Geraghty, Campaign Spot

Specter Switch: Great News, But Now a Dem Primary – David Sirota, Huffington Post

Arlen Specter, Democrat – Ben Domenech, New Ledger

When Specter Tipped His Hand – Noam Scheiber, The Plank

Specter's Switcheroos – Jonathan Tobin, Contentions

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