WASHINGTON – Mitt Romney clinched the Republican presidential nomination Tuesday with a win in the Texas primary, a triumph of endurance for a candidate who came up short four years ago and had to fight hard this year as voters flirted with a carousel of GOP rivals.

According to The Associated Press count, Romney surpassed the 1,144 delegates needed to win the nomination by winning at least 88 delegates in the Texas primary.

The former Massachusetts governor has reached the nomination milestone with a steady message of concern about the U.S. economy, a campaign organization that dwarfed those of his GOP foes, and a fundraising operation second only to that of his Democratic opponent in the general election, President Barack Obama.