Yes, Obama's going to nominate Gregg this morning. So let's look at Gregg. From the Heritage Foundation, Gregg and a Blue Dog introduced legislation for Social Security "carveouts"* back in 2000:

Carve-out Accounts
The other alternative is to fund an individual Social Security account by diverting, or "carving out," some portion of the 10.6 percent of income (including the part that an employer pays on behalf of the employee) that Americans now pay for Social Security retirement benefits. In the legislation introduced by Representatives Jim Kolbe (R-AZ) and Charles Stenholm (D-TX), 16 and that introduced by Senators Judd Gregg (R-NH) and John Breaux (D-LA), 17 8.6 percent of income continues to go to Social Security, while an amount equal to 2 percent of income funds a personal retirement account.

I guess, back in 2000, that might have looked pretty good to somebody who wasn't paying attention. See Dean Baker in 1998 on Gregg's problems with the numbers:

I don't think I've ever read more ridiculous justifications than I'm reading right now about why it was a "good idea" for Obama to appoint a Republican to Sec. of Commerce, and agree to have a Democratic Gov replace him, with another Republican.

Because the massive filibuster-proof uberliberal majority Dems have in the Senate is so Huge! Or something...