How? What will the headlines say? "Republicans Still Mad About Getting Their ***** Handed To Them 6 Months Ago!"? Extra, extra, read all about it.
This'll be old news by then on the campaign trail, and if the Republicans are stupid enough to want to make their campaigns about a fight they already lost, I'm sure the Democrats will be delighted to let them. The only way this would be newsworthy this fall is if there were some actual, measurable effects of the legislation at that point, and it's very unlikely there will. Some taxes will have kicked in, but if the economy is doing well by then, the taxes won't seem very important. None of the new regulations will have gone into effect, so nobody will be able to debate about them. What will make this bill still newsworthy 7 months from now?
People vote in accordance with whatever they happen to be most scared of or ****** off about in the ten days prior to the election. In today's world, there will be no shortage of things between now and November that will have people plenty scared and plenty ******. Health care will be a minor factor, nothing more than a talking point to whip up the rabid conservative base that's already going to vote republican anyway. Most moderates and independents are going to be a lot more worried about Iran or Afghanistan or the economy by then, or any one of a hundred other things that could pop up this summer. Democrats, on the other had, are likely to be invigorated by it, because their legislators will be able to point to it as something they accomplished.
This isn't exactly a slam dunk for the dems in November, but overall it will be more of a positive than a negative.