In 1910 no women and only men who met the property qualification could vote. The total poll was just over 200,000 votes.
Interesting point. I will concede that 'fringe' sentiment for a Republic and full independence is an inapt description.
Let me say therefore that there was a significant underbelly of that sentiment for a Republic but as you point out it was not organised and as such remained effectively dormant. A sleeping dog so to speak.
It was the actions of Irish Unionists and the British government in usurping the Home Rule Act, that kicked the sleeping dog. The Suspensory Act, introduced on the same day to suspend Home Rule, on 18 September 1914. It was debated in House of Commons on 31st August 1914 and it was clear then that Home Rule parliament would be suspended to avoid "any controversial matter... to place any parties in worse position than before the War broke out" - Asquith, succumbing to Ulster Volunteers threats of violence, in my opinion.
Following this, on 5th September 1914 the IRB Supreme Council met and agreed to plan for a rebellion.