Have a look at our county's voting numbers on the Secretary of State web site. About 44% of the voters waited until election day neared before sending in their ballot. I'm hopeful they also waited to make their choice but there's no way of knowing for sure.
But look how many made up their minds up to three weeks beforehand. I'm not going to characterize them, but it seems like it would be prudent to wait. A lot can happen in three weeks during an election cycle.