"All of us, wherever you live, we can recognize that if immigration is a problem, it is the best possible problem for this country," O&R said in his Thursday video.
Mr. Trump, in turn, laughed at Mr. O & # 39; Rourke for turning a losing campaign into a springboard for a presidential nomination. "Hey, you should win to run," Trump said.
But the Democratic primaries could present unique challenges to Mr. O & # 39; Rourke.
It is an open question if he will be able to scale his skeletal organization and deliver control to the type of political professionals he has largely avoided in his Senate race. The official anticipation of Mr. O & # 39; Rourke was very improvised on Thursday, partly because he personally directed much of the planning.
Yet he enjoys the support of many former helpers of President Barack Obama, some of whom are tacitly and others are still full-throated, and has relied on the advice of a number of Obama strategists, including the 2008 campaign manager, David Plouffe. (Mr. Plouffe, however, has no intention of formally participating in the tender on behalf of any candidate.)
But unlike Obama, who ran in a year when the war in Iraq was the only problem Priority politician in the race, Mr. O & # 39; Rourke is looking for the presidency at a time when his party is stumbling to the left across the board. He will be immediately under pressure to expand the sometimes vague liberalism that has colored his public life.