Bachmann Tea Party debate
Michele Bachmann participated in a Tea Party-sponsored debate in Miami earlier this month. Reuters

Michele Bachmann said at a forum on Thursday that social conservatives should not settle for a presidential candidate who does not share their views.

But what views are those, exactly?

The Minnesota congresswoman called herself the true social conservative in the Republican race. She had particularly harsh words for Mitt Romney, who has grown increasingly conservative in the past few years but is still struggling to shed a moderate reputation from his time as governor of Massachusetts.

Most people who consider themselves social conservatives will probably be choosing between Bachmann and Rick Perry, both of whom have taken solidly conservative positions on issues like evolution, same-sex marriage and abortion (no, no and definitely not).

Here's the problem, though: no one really agrees on what a social conservative is, not even the people who identify as one.

Some people say that social conservatives oppose government interference in state and individual affairs. Others say they want to uphold traditional values, such as preserving the nuclear family model and the sanctity of life.

Some define social conservatism as both of those things, but that becomes problematic when a social conservative urges increased government intervention in order to protect a traditional value -- for example, a constitutional amendment banning same-sex marriage, which both Bachmann and Perry support.

Small-government conservatives are sure to be a powerful demographic both in the Republican primaries and in the general election next year, given how vehemently conservatives of all stripes have condemned what they see as governmental overreach by President Obama. And if by social conservatives, Bachmann means small-government conservatives, she is certainly on the right track to gain their support.

In particular, her persistent attacks on Perry's old policy requiring sixth-grade girls to get an HPV vaccine have endeared her to some libertarian-leaning Republicans, although she sabotaged some of her advantage with her unsubstantiated remark that the HPV vaccine could cause mental retardation.

If she is targeting traditional-values social conservatives, she faces a tougher road, because this is not nearly as large a constituency as many people think. There are, of course, highly vocal groups that oppose abortion, same-sex marriage, evolution lessons in public schools and the like, but in spite of their prominence in the media and in political campaigns, they are actually a minority even among Republicans.

A recent New York Times-CBS News poll illustrated this very clearly. For example, among the general electorate, 73 percent of voters said abortion should remain legal, and even among Republicans, a majority -- about 60 percent -- said it should remain legal. Two-thirds of the general electorate thought either marriage or civil unions should be allowed for same-sex couples, and about 60 percent of Republicans thought so, too.

But if Bachmann is lumping together both groups of social conservatives, she will have problems later on, because she won't be able to define her own base.