On Friday, Irish voters began heading to polls to help decide whether same-sex marriage should become legal in the country. If more than 50 percent vote "yes," Ireland's conservative constitution will be rewritten to add a clause that would allow same-sex marriage: "Marriage may be contracted in accordance with law by two persons without distinction as to their sex.”

Ireland could very well become the first country in the world to legalize gay marriage by popular vote, and most polls suggest a lead for the "yes" vote. But things are close and there's an added complication: Voting must be done in person at specific polling stations.

That's an issue for those who work in the capital of Dublin and who must travel to rural areas to vote. But it's even more dramatic for the many Irish citizens who live abroad and want to vote. According to the Irish Times, 250,000 people emigrated from Ireland after the 2008 financial crisis, heading abroad to find better economic opportunities. In a country with a population of 4.5 million, that's a big number.

More than 70 percent of those who left after 2008 were in their 20s. That could be important to the outcome of the vote: One poll released this month found that 90 percent of those ages 18 to 35 supported gay marriage, though not all intended to vote.

It's unclear how many Irish who live abroad are making their way back to vote. But judging by the success of #HomeToVote, which has been shared on Twitter almost 40,000 times in the past 24 hours, plenty of people are making the journey and sharing their experiences on social media.

For many, it was a very moving experience.

And the Irish wit was on display too.

Polls are staying open from 7 a.m. to 10 p.m. Friday to accommodate the voters. Results are expected Saturday.

See also:

Ireland could be first nation to legalize same-sex marriage by popular vote

Where acceptance of homosexuality has and has not changed around the world