More than 10,250,000 American seniors are enrolled in the popular Medicare Advantage program, which lets them choose to get their Medicare benefits through private insurers. It's been widely reported that seniors' Medicare Advantage benefits would be cut under Obamacare. What hasn't been widely reported is by how much.

According to Congressional Budget Office (CBO) projections, in its real first ten years (2014 to 2023), Obamacare would cut Medicare Advantage benefits by $214 billion. Medicare Advantage plans vary by company and region, so cuts would vary from person to person. But, on average, Obamacare would cut Medicare Advantage enrollee's benefits by $21,000 — per person.

Now, $21,000 may be a reasonable price to pay for a new car, but it hardly seems like a reasonable amount to expect someone to contribute to Obamacare — especially when he or she wouldn't get anything in return.

To be fair, not all seniors would be forced to make this contribution.  Thanks to the "Gator Aid" deal that Sen. Harry Reid struck behind closed doors with Sen. Bill Nelson, seniors in South Florida would be exempt.

But most seniors across America wouldn't be so fortunate, including those in Massachusetts — who'll have the first chance to weigh in on Obamacare in the voting booth.