Senate Democrats are worried they may be delayed debating the merged health care bill Senate Majority Leader Harry Reid sent to the Congressional Budget Office Monday while they wait for the CBO to score the measure.

Roll Call is reporting (sub. req.) that senators are concerned the score may not be available for another week and a half, which would postpone the debate beginning late next week.

As Brian detailed yesterday, there are plenty of unanswered questions about the bill.

TPMDC interviewed former CBO chief Doug Holtz-Eakin, who served as an economic adviser to the McCain campaign last year.

"It's so unclear to me what actually is being proposed," he told us, adding he was surprised any senators have been able to take sides since the details are scarce. "There are a million questions."

Here's his checklist focused on the public option opt-out:

Do states have to pass a law or does the governor make the decision? When do they need to decide whether they are opting out? Can they opt back in if they change their mind? What if an election or term expiring or change in political landscape occur? Does the state get a second chance? Is it subject to state taxes? What if someone lives in a public option state and then moves to a state which has opted out?

Holtz-Eakin said the lack of detail isn't unprecedented since CBO has yet to score the bill. Senators can't retail the particulars of the measure in the press until they have that information, he said.

Democratic members of the Senate have been answering citizen health care questions via video this week, but none seem to address the public option structure yet.