Massachusetts voters go to the polls today to elect the late Ted Kennedy’s senate replacement. They also hold the fate of Obama’s healthcare reform programme in their hands.

From a 30 point lead in the polls Democratic candidate Martha Coakley’s ratings have plummeted. Recent polls have put Republican candidate Scott Brown ahead.

The result of today’s election goes well beyond whether True Blue Massachusetts sends a Republican back to the Senate however. If Brown is victorious the Republicans will have 41 out of 100 senators; the number required to talk out a bill and prevent a vote.

Democrats have held together their coalition of 60 over recent months. But only just. As it is, it includes two independents and the interim successor to Kennedy, Paul G Kirk.

Little wonder that both parties have wheeled out the big guns. The ‘will he, won’t he?’ question was answered emphatically over the weekend as Obama hit the campaign trail in support of the flagging Coakley. Democratic strategists must be reeling. We can be certain that a Republican sitting in Ted Kennedy’s former senate seat was not on the list of likely obstacles to healthcare reform.

The irony of course, is that one of the major causes of this damaging swing against the Democrats is the proposed changes to healthcare itself. The issue which Ted Kennedy called the “the cause of my life” is unpopular. In Massachusetts a recent poll showed that 51% of people oppose reform and 61% think that the nation which spends more on healthcare than almost any other county on the planet cannot afford the proposed changes.

If Scott Brown wins, the programme, which aims to extend healthcare to millions of Americans who are currently without cover and to prevent insurance being refused to those who have pre-existing conditions, could be in jeopardy.

Washington pundits are currently speculating wildly about the options open to Obama. These range from watering the bill down, pushing it through before Brown takes his seat (he could be delayed if the fight is tight enough and the courts get involved), getting the House of Representatives to vote on the version already agreed in the Senate or pursuing a legislative strong-arm tactic called reconciliation, which requires the support of only 51 senators.

Even if Coakley wins – unless she wins big –  we can expect some rowing back. Moderate democrats with one eye on the mid-term elections in November will become even more cautious about a policy opposed by a majority of Americans.

The prognosis for meaningful healthcare reform in America is, unfortunately, looking grim.

Professor David Kerr is the Research Director of Sidra Medical and Research Center and Professor of Cancer Therapeutics and Fellow of Corpus Christi College, University of Oxford