Ancient Influence

Political Card - Worth 1 Vote. Called by any vampire at +1 stealth. Successful referendum means each Methuselah may choose a ready vampire he or she controls. Each Methuselah gains an amount of pool from the blood bank equal to his or her chosen vampire`s capacity. Each Methuselah then burns 5 pool. Only 1 Ancient Influence can be played in a game

The last sentence, "Only 1 Ancient Influence can be played in a game."

Is this successfully played (not blocked) or just one attempt?

The card is played when the action is announced, so it cannot be played again even if it is blocked, put back in your hand from Delaying Tactics, or canceled by Direct Intervention, etc.

Please note that this wording is subject to change some day or another (and be consistent with the other "played or called" cards).