Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Washington (CNN) Texas Sen. Ted Cruz's wife Heidi on Tuesday reportedly tried to energize supporters by comparing her husband's failure to clinch the Republican presidential nomination this year to how long it took for abolitionists to end slavery. The comments came in a conference call with the Cruz campaign's National Prayer Team, as transcribed by Texas Tribune reporter Patrick Svitek. "Be full of faith and so full of joy that this team was chosen to fight a long battle," Heidi Cruz said. "Think that slavery -- it took 25 years to defeat slavery. That is a lot longer than four years. ... We're going to keep moving forward."Heidi Cruz compared her husband's failure to win the GOP nomination to the fight to end slaveryThe comments came in a conference call with the Cruz campaign's National Prayer Team 
 Question:RELATED: _ not ruling out re-entry into race if path opens.

Ted Cruz