In a First Past The Post electoral system, has anyone ever created or significantly supported a political party they profoundly disagree with in order to split the opposition vote?
Additional background: this question about history was born out of some musings about current politics in the United Kingdom. Suppose hypothetically that the outcome of Brexit all came down to anti-Brexit MPs winning a general election. Suppose also that someone extremely rich wanted to swing the outcome against Brexit as much as they possibly could. One hypothetical possibility is that instead of supporting an anti-Brexit party, they could actually found a new, pro-Brexit party standing in all 650 seats. Let us call this party the "Moderate Right". Suppose it supports a moderately soft Brexit but otherwise has policies very similar to the incumbent Conservative party, and policies as different as it can from all parties in the Remain Alliance. Then, possibly, it may split the pro-right wing and pro-Brexit vote between the Conservatives, Brexit Party, and Moderate Right, paving the way for a Remain Alliance victory in a First Past the Post electoral system.
Has something of this nature ever been attempted at some point in history anywhere in the world?