Personally, I think that analytical intelligence makes people more conservative whereas what is colloquially referred to as "emotional intelligence" makes people more socialist, which explains why women are more left wing than men. If the woman hadn't gained the right to vote, the Republicans would have won every election since 1950 with the exception of Goldwater in 1964.

Also, the Americans really should learn what the word liberal means. Liberalism = Gladstone/Hayek.

For what it's worth, I believe that intelligence is genetic but whether you are a rational or an emotional person is a question of nurture rather than nature.

Genetic determinism is a dangerous thing to put faith in, but it is obviously true that your genotype will slant the probabilities in a particular direction.

You're more likely to be open-minded and have met people from a range of backgrounds, if you have a genetic predisposition to go around trying new things, and that's a trait that sounds like it could reasonably be expected (a) to be genetically modulated and (b) for those genes to show variations between individuals (a healthy population will contain both risk-takers and cautious individuals; that gives resilience against a range of threats as well as the possibility of community expansion; there'd be no evolutionary benefit in eliminating variation by reverting to an entirely risk-averse or entirely risk-seeking population, the former being unable to take advantage of new opportunities and the latter being highly vulnerable).

Could having met a lot of people from a range of different backgrounds make you more left-wing? Yes, I think that's reasonable. Not just by empathy, but also, because you realise that you too could end up in a different life situation where a set of socio-economic policies primarily benefitting the elite rather the poor could hurt you; you're more likely to seek a social safety net.

BOTH tendencies to conservatism & liberalism have been cited as being genetic. While it's fun to make up definitions of words, according to Chambers, "conservative" is defined as " tending to support or preserve established views, customs, institutions; opposed or averse to change; traditional.." whereas liberal is defined as "generous, nobleminded, not bound by authority or traditional orthodoxy, looking to the broad rather than the literal sense, suitable for a freeman"...
looking at this, I suspect MOST people fit in either category issue by issue, rather than one rigid line. The trouble is, political parties and politicians use words cleverly to push people in various directions because the average man and women, both conservative AND liberal, tend to think less than they should, and act more from emotion. The idea that men are more analytical mentioned in another post is laughable; they are just as emotional, but CULTURE determines the emotions they are allowed to express. Watch a crowd that is being roused and the truth is there LOL
Genetics might predispose a person to something but environment, culture, REASON and choice to think things through or not is what drives the persons politics.

Liberalism is a disease and can only be treated effectively by voting liberals that are IN office, out, and never vote another one in.