As the nation prepares for the upcoming midterm elections, it is unclear what effect the recently founded Tea Party movement will have in the voting booth. Here, William Mayer, associate professor of political science at Northeastern University, looks at the rise of the Tea Party movement and its potential effect on electoral politics in 2010 and 2012.

Do you expect the Tea Party movement to have a continuing impact on how the midterm elections shake out?

The Tea Party movement has already had a substantial impact in the Republican primaries, leading to the nomination of a number of candidates who wouldn’t have come close to success in a more typical year. It has also proven to be a potent source of volunteers, activists and contributors. The key question — still to be answered — is whether some of those candidates are seen to be so extreme or unqualified as to be incapable of winning the general election, even against rather weak Democratic opposition. In the longer term, no matter what the Republicans actually do in the next Congress, it is clear that the Democrats and many of their allies in the media will attack the Republicans for being “too extreme.”

Why do you think the Tea Party movement has appealed to so many supporters?

The United States has long been known as a country that is suspicious of big government, with a much more limited public sector than other industrial democracies. Obama and the Democrats, in my opinion, dramatically misunderstood the meaning of the 2008 election, thinking that the public had given them a mandate for all sorts of new government initiatives when all the voters were really saying was that they were dissatisfied with George W. Bush. So it’s no great surprise that the Obama policies have generated a strong counter-reaction.

How has the reaction to the Tea Party from both Democratic and Republican leadership evolved over time?

The Republican leadership has become gradually more welcoming to the Tea Party movement — for the obvious reason that Tea Party candidates keep winning major Republican primaries. At this point in the 2010 election cycle, almost the only thing the Democrats can do is attack the Tea Partiers for being too extreme or even racist. I don’t think that tactic will work very well for the Democrats, and it won’t surprise me if they have to develop a new approach after the election.

When was the last time a movement like this shook up the traditional two-party system?

Perhaps the best recent parallel to the Tea Party movement is the anti-war movement of the late 1960s and early 1970s. Like the Tea Partiers, the anti-war movement generated a lot of enthusiasm and activism, though somewhat less support among the public as a whole. Also like the Tea Party movement, the principal electoral impact of the anti-war movement occurred in one of the parties — in that case, the Democrats. The anti-war forces “took over” Democratic primaries and local Democratic parties and replaced older, more traditional Democrats with anti-war candidates, culminating with the presidential nomination of George McGovern in 1972. Though McGovern was soundly defeated, the Democratic Party has never been the same.

What are the prospects for the Tea Party movement’s future?

The future of the Tea Party depends on two things: how successful their candidates are in the 2010 general elections; and, even more, how those Tea Party candidates who do win behave in government. The principal danger for the Tea Party, in my opinion, is that, much like both the Obama people and the Republican Congress of 1995–1996, they will substantially over-interpret the meaning of their election and govern in a way that turns off lots of moderate and independent voters — and thus guarantees the re-election of Barack Obama.