Should win at least 2, likely 3. Look at his recent losses on clay:
2012: 1 - Verdasco - blue clay; doesn't really count/have bearing on usual clay results. Won 4 titles.
2011: 2- Novak in peak 2.0 mode. Won 3 titles.
2010: 0 - Won 4 titles.
2009: 2 - Soderling; Federer. Won 3 titles.
The top seeds in Chile: Nadal, Monaco, Chardy, Andujar.
Top seeds in Brazil: Nadal, Almagro, Monaco.
Top seeds in Mexico: Ferrer, Nadal, Almagro.
Ferrer and Almagro only real threats - would be final if in Brazil and SF/F in Mexico. He'll have been practising on clay for a month before Chile. Is practicing in Barcelona with Pere Riba etc. i.e, ATP level players back from AO rather than just juniors in Mallorca and will also play doubles as well as singles. Clearly he'll want to win too rather than just tanking like he's sometimes happy to do at Queens etc.
All in all, think it'd be surprising if he wins nothing at all. Not that shocking if wins all 3.
Add to the 09 losses that before the Federer match, he had the longest three set match ever lasting over 4 hours. And with Soderling he was injured.