I'd love to see something concrete about this. So far no one has been able to provide any proof. All we know is they met with Ward to interview him, as they do with most 1st round candidates. They've also met/are with Sanders, Dart, Graham and pretty much every player in the top 15.
So far, I think people are just seeing "Saints interviewed..... such and such" and interpret that as "Saints want to draft", which is utter speculation (and the speculation happens every year it seems).
I'm positive the saints have also contacted the Titans. I'm also positive they've contacted the Browns, Giants, Patriots, Jaguars, Raiders, Jets and Panthers and likely several teams behind them. The purpose to is gather intel on trade interest, compensation expectations etc this way closer to the draft some of these deals get worked out incase a scenario unfolds where the Saints want to trade up, the compensation is already printed and the haggling done and GM's either have to give a go or no-go. It's how these draft trades get done in real time as the draft is taking place.
Likewise, many, many teams are contacting the saints and asking the saints for their trade interest, compensation expectations etc.
It does not mean, whatsoever, that the Saints "want" the first overall pick, nor does it especially mean "they want to trade for the first round pick for Cam Ward". Whoever says that is taking a very common thing that happens every draft and making up speculation.
All that's taking place, is every NFL team is communicating with every other NFL team to set an expectation in trade value for every slotted pick to set a general precedent on compensation value for every slotted pick. Later, as we get closer to the draft, the haggling negotiations will begin with every other team so that deals are in place incase teams decide to trade up or down.