One name to watch-- the name to watch, according to this article-- is Beto O'Rourke.
Beto tried to take Ted Cruz' senate seat in the past election. O'Rourke fell short, 51% to 49%. So why is a guy who didn't even win his senate race viewed as such a contender? Well, it's not that he lost, it's how he lost.
I agree that O'Rourke did an impressive job in turning what is normally an easy win for the republicans in conservative Texas into a competitive race. However, I would be quite hesitant in giving him a presidential run just yet....
Cruz is not exactly a likable politician, and while Trump has a higher approval rating in Texas than in the rest of the country, he doesn't have majority support. Plus, the Democrats spent a whole lot of money trying to win the seat.
Of course, a Democrat from a traditionally red state might have an advantage in a presidential election, since they might be able to pick up some electoral college votes that would normally be a hammerlock for the republicans.
https://www.star-telegram.com/news/state/texas/article218605715.htmlPersonally I rather like Cory Booker... he's got senate experience (including holding positions on the high profile foreign affairs and judicial committees), he's seen as a political moderate (in favor of things like abortion and gay rights, but also has pro-business policies, especially in the technology area.)
The only problem with him is that he isn't married. While I don't think that would actually be a problem when running the country, I can see the republicans resorting to smear tactics. "He's not married! Must be a pervert".