Though not as important as the presidential election, polls in the various Senate races are beginning to point to the possibility of 60* Democratic Senators in January. This would dramatically change the way laws are passed in the Congress for the next two years, which I'll go over in the rest of this paragraph. The Speaker of the House can more or less call for a vote whenever she wants, because through her control of the Rules Committee, she can end debate and force a vote. All it takes is the Speaker and half of the remaining 434 Representatives to get a bill passed in the lower house. In the Senate, each and every Senator can talk as long as he or she wants before a bill is voted on, unless 60 Senators vote for cloture, meaning an end to the debate. If fewer than 60 vote to end debate, the opposing minority (i.e., the Republicans, these days) can go on talking all day and all night long, keeping a vote from being held. This is a filibuster. This system is meant to to allow a minorty party to prevent a thin majority from completely running roughshod over the process.
For example, let's assume a President Obama (be still my heart!) was dealing with the Senate as currently composed, with 51* Dems and 49 Republicans, on the issue of Obama's health care proposal (btw, being in the health field, I do feel obligated to talk about the candidates' health care reform proposals, which are radically different both from each other and from the current system. So stay tuned!). If the 51 Democrats were for it and the 49 Republicans were against it, it wouldn't pass, because Obama and his allies could not get the 60 votes needed to get cloture, ending debate and allowing the vote to occur.
In the current election, 37 Dems, 26 Republicans and the 2 Independents do not have to run for re-election this year, while 12 Democratic and 23 Republican seats are up; there's so many more Republican seats up because the Democrats got their asses handed to them in '02, in the lead-up to the Iraq war. If the Democrats win in 21 of these 35 seats, they would then have the magic 60, meaning that they could push through any bill they wanted without any Republican input at all.
Based on the polling-analysis model over at fivethirtyeight.com, the 12 Democratic seats up for election are all safe, meaning they need to win 9 currently-Republican seats to reach 60. Picking up seats in Virginia and New Mexico seems to be a mortal lock. Colorado, New Hampshire and Alaska (depending largely on the federal corruption trial of Ted Stevens) are looking good. Oregon and North Carolina currently appear to be 50-50. And Republican seats in Minnesota, Missippi and Kentucky are vulnerable. fivethirtyeight's model calculates, at present, about a 1 in 6 chance that the Democrats will reach 60. Given Obama's massive voter registration and GOTV (get out the vote) efforts, and possible coattails if his poll numbers remain as strong as they are, I'd put the odds a bit better than that.
So, long story short, the fate of Obama's health care plan might depend on Al Franken.
*Actually, right now there's 49 Democrats and 49 Republicans in the Senate, along with 2 Independents, Joe Lieberman of Connecticut and Bernie Sanders of Vermont, who are for all intents and purposes Democrats. Even if Lieberman were to break from the Democratic Party more fully than he has, he still is, in terms of domestic policy at least, in line with the Dems and would often be a reliable vote for cloture.