Josh Marshall thinks so:

And here's the thing to keep in mind. If Scott Brown were to pull off an upset that would end Health Care Reform, pulling Dems back to 59 seats and preventing final passage of the bill.

Not saying this is a likely scenario. But the stakes are staggering.

This projection is based on new polling released this morning by Rasmussen Reports showing Democrat Martha Coakley leading Republican Scott Brown by a surprisingly narrow 50 percent to 41 percent margin in the Massachusetts special Senate election to be held January 19.

Leaving aside Democratic complaints about Rasmussen polling and even the fact that this poll was only in the field a single day (and virtually every pollster other than Rasmussen won't release single-day numbers due to the inherent methodological concerns), is it really the case that a Brown win would kill healthcare reform?

Short answer: Not necessarily. While a Brown win would little doubt provide evidence of momentum behind the Republicans, thus inhibiting the path towards passing healthcare reform on a political level, it would not block the Democrats from being able to enact the legislation without having to once again get 60 votes in the Senate (which they would no longer have without GOP support should Brown win). Were the House to pass the exact version of healthcare reform already passed through the Senate, that bill would go to the President's desk to be signed. No need for another cloture vote in the Senate. No killing the bill just by changing the make up of the Senate.