For conservatives and Republicans, the next few days and weeks will be ones to savor. Scott Brown’s win yesterday will force Democrats to consider just how many seats they’re willing to lose to complete a health care bill. Jim Webb, Brad Ellsworth, Evan Bayh, Joe Lieberman, and Anthony Weiner were all willing to come out and call for a rethink yesterday – before the results in Massachusetts were really clear. No less a liberal leader than Barney Frank thinks it’s time to sue for peace.

It will be almost impossible for Democrats to continue with health care as if nothing happened.

Beyond the effect on the policy debate, the Massachusetts result really does show that there’s no such thing as an unwinnable race this year. Republican candidates who had made decisions not to tilt at windmills, are now reconsidering. According to the Politico, that may lead one of the House’s best-known and most trusted conservative leaders to challenge one of the Senate’s safer Democrats:

At least one Republican might do more than cheer for Massachusetts: House GOP Conference Chairman Mike Pence is now considering a campaign of his own against Sen. Evan Bayh.

The outspoken conservative could effectively clear the Republican primary field and give his party a top-tier opponent for one of the best funded Democratic incumbents in 2010.

Pence issued a statement on the Massachusetts race, saying the “American people are telling Washington, DC enough is enough. In this special election in Massachusetts they have sent a deafening message to the political class.”

If Pence gets into this race, Bayh will have a top-notch opponent who can raise money, and who’s in tune with the mood of the voters. In a state that looks likely to be deep-red again, Bayh will face all he can handle.

And in the next few weeks, we’ll likely see many more top-notch GOP challengers emerge for many races.