Time is running out for GOP candidates in a race that is rapidly leaning towards Mr Donald Trump.
Mr Trump and rivals take centre stage at a debate in Houston on Thursday (Feb 26). On stage with Mr Trump will be US Senator Marco Rubio, US Senator Ted Cruz, Ohio Governor John Kasich and retired neurosurgeon Ben Carson.
Mr Trump, 69, has won three of the first four contests in the nomination fight for the Nov 8 election to succeed Democratic President Barack Obama.
After easily defeating his rivals in Nevada on Tuesday, the New York billionaire businessman is in position for more victories on March 1, when a dozen states will vote on "Super Tuesday".