As long as you are credible and have a smoothly running testnet notary. However if the choice is between someone without the real server ready vs. one that has it ready and all else is equal...
At this point I dont think we will have more than 64 candidates though, so it should be ok.
Important thing is to be active and interact with the other testnet notaries. There will be a non-binding peer ranking among the testnet notaries for all the other notaries. This way the electorate can see how each testnet notary is viewed by the others on several scales, ie technical competence, helpfulness, reliability, promptness, etc.
In addition to objective metrics I think having subjective metrics from the peer group will be useful. While in some sense the notaries are competing with each other, they are much more cooperating with each other as the majority of the testnet notaries will become the official ones. At least at first.
Now it is possible some large investors or investor groups will want to vote in their own notary operator, maybe simply to increase their ROI or more strategically to ensure that any 51% attack is one notary node more difficult to achieve. Controlling a notary node wont really provide any other advantage that I can see to any stakeholder as there is a separation of powers and after a few blocks it is notarized by bitcoin