By Emily Stephenson
HUDSON, New Hampshire (Reuters) - Republican presidential candidate Ted Cruz sought on Tuesday to link his rival Donald Trump to Democrat Hillary Clinton, saying it would make her supporters happy if the real estate mogul were to win the Republican nomination.
Trump had cited constitutional law professor Laurence Tribe in arguing that because Cruz, the U.S. senator from Texas, was born in Canada, he might not be eligible to be U.S. president.
"It is more than a little strange to see Donald relying on as authoritative a liberal left-wing judicial activist Harvard law professor who is a huge Hillary supporter," Cruz told reporters after a rally at a gun range in New Hampshire.
He said in the last couple of presidential elections, Democrats were able to run against the Republican of their choice, leading to two victories for President Barack Obama.
"It starts to make you think, gosh, why are Hillary's strongest supporters backing Donald Trump?" Cruz said.
Cruz also deflected questions about his eligibility to seek the White House in the November, 2016 election, saying the legal question was settled.
On Twitter on Tuesday afternoon, Trump called the citizenship issue a “serious problem” for Cruz and linked to an article by Tribe in the Boston Globe that said it was an open question whether Cruz was eligible to be president based on the fact that he was born in Canada.
The Cruz-Trump rivalry has been intensifying ahead of the Feb. 1 Iowa caucus, the first step in the presidential nominating process. Cruz leads in the polls in Iowa, while Trump holds a lead in national polls and in New Hampshire, which holds its primary on Feb. 9.
For more on the 2016 presidential race, see the Reuters blog, “Tales from the Trail” (http://blogs.reuters.com/talesfromthetrail/).
(Reporting By Emily Stephenson; Editing by Caren Bohan and David Gregorio)