Chris Christie called it "the dumbest idea anybody ever had."

Mitch Daniels has criticized it.

And according to the chairman of the Vermont Republican Party, it's "water torture."

The slow-burning Republican presidential nominating process is facing scrutiny and sharp criticism as the increasingly bitter GOP primary fight threatens to drag on into the spring and perhaps the summer.

The anxiety is coming from Republicans, many of them supporters of front-runner Mitt Romney, who worry that the drawn-out fight for delegates has forced the GOP candidates into costly intra-party warfare, while President Barack Obama is free to raise vast sums of money and strategize for the general election.