In Christie, Trump also gained a powerful surrogate responsible for the lowest moment in the campaign of one of his last Republican adversaries: Marco Rubio.

The New Jersey governor also opened a door for other Republican Party elites, who spent recent days rushing to boost Rubio, and invited them to walk through. If beating Hillary Clinton outweighed all other factors, as the New Jersey governor argued, then other objections to Trump’s campaign—such as his bombastic and nativist rhetoric—should take a back seat. As a twice-elected governor of a blue state and former chairman of the Republican Governors Association, Christie could serve as Trump’s ambassador to establishment donors, lawmakers and behind-the-scenes operators across the nation.

Wasting no time in showing what he brings to the campaign, Christie seized his new role as Trump standard bearer with zeal, undermining Rubio’s core pitch for his nomination—his electability—and belittling him as a performer delivering “one act after the other.”

“The single most important thing for the Republican Party is to nominate the person who gives us the best chance to defeat Hillary Clinton,” Christie said at a Fort Worth news conference with Trump. “I can guarantee you that the one person Hillary and Bill Clinton do not want to see on that stage come next September is Donald Trump. They know how to run the standard political playbook against junior senators and run them around the block. They do not know the playbook with Donald Trump, because he is rewriting the playbook.”