If you go to the following site, you will see an ad for 15,000 miles if you sign up for Citicards Platinum. There is no fee the first year. Note that this card offers quarterly reduced mileage awards, for instance, in the current quarter you can get a ticket to SDQ, POP, or LRM for only 17,500 miles. In the next quarter, Oct - Dec there are no deals to DR, but plenty to South America for 22,500 miles. Typically they have some type of reduced award to DR, but usually not the last quarter of the year.
http://www.citibank.com/us/cards/cardserv/worldcard/index.jsp
http://www.citibank.com/us/cards/cardserv/worldcard/index.jsp