Politico' s Manu Raju writes:

Political insiders in Washington and New Hampshire say Sen. Judd Gregg's nomination as Barack Obama's commerce secretary is nearly a "done deal" - with Republicans signing off as long as Gregg's Senate seat goes to another Republican, and Democrats in agreement as long as that Republican is either a caretaker or somebody they can beat in 2010. ... Democrats say there are plenty of candidates for the caretaker role, including Peter Spaulding, who sits on New Hampshire's Executive Council; Bonnie Newman, a moderate Republican who was chief of staff to Gregg when he served in the House and an interim president at the University of New Hampshire; former state House speaker Doug Scamman; the 86-year-old former governor, Walter Peterson; and state legislator Liz Hager, a Republican who supported Obama in November and has told local reporters she'd serve for only two years.

It's a real shame that Gregg will almost certainly exit the Senate. He's a pretty solid conservative from New England, and current polling indicates that he would win a close 2010 race. It would be an even greater tragedy, however, if Gregg assents to the selection of a liberal Republican to serve as caretaker for the next two years. This afternoon, Gov. Lynch issued a statement pledging that he would appoint a Republican to fill Gregg's seat. Patrick Ruffini argues that Republicans should drive a hard bargain:

we need to insist not only that Gov. Lynch appoint a Republican, but that he appoint a Republican from a list of three candidates prepared by Republican leaders in the legislature and the New Hampshire Republican Party -- preferably a strong Republican who would run in 2010. Gregg was about as conservative as you get for New England, and any replacement selected by a Democrat is almost guaranteed to be worse. This is not unprecedented. Wyoming law required the Democratic governor pick from a Republican-prepared list of Senate candidates in 2007. Given the extraordinary nature of this appointment, Democrats should have no problem agreeing to the simple request that Republicans have a voice in choosing New Hampshire's Republican Senator.

There are three issues on which I can see a Republican-led filibuster successfully blocking Democratic legislation: card-check, nationalized health care, and taxpayer-funding of abortion. On each of these issues, at least one or more Republican senators will break rank, but there are also a few Democrats who could potentially back a Republican filibuster. These are the kind of votes that could hinge on one mavericky senator from either side. Republicans and Gregg would be foolish to settle for a Republican replacement who would toe the liberal line on issues like these where the threat of a GOP filibuster actually matters.