Mitt Romney is about to become mathematically inevitable.

When Texas ends its GOP primary tonight, the presumptive nominee is all but certain to clinch his party's presidential bid, surpassing the 1,144 delegates he'll need to secure the GOP nomination at the Republican National Convention in Tampa in August.

Romney will need to secure a little more than 38 percent of the vote in Texas to reach the magic number. He has taken more than 60 percent in every primary since April 24, when he fell short of that mark in Pennsylvania and Delaware, two weeks after Rick Santorum dropped from the race.

Romney controls 1,086 delegates, according to the latest ABC News estimate. To clinch the nomination, he'll need to win 58 of Texas's 155 delegates.

It has been a long campaign for Romney, who has shared front-runner status since its beginning. In total, 48 contests have been held, not counting Missouri's nonbinding primary and caucuses.

Romney has won 36 of the contests, collecting 6.8 million votes, 48 percent of the popular vote in GOP primaries across the United States and its territories. His nearest competitor, Santorum, won 10 contests, 253 delegates and 3.5 million votes for a 25-percent share of the overall popular vote. Newt Gingrich won two states, 131 delegates and 18 percent of the votes; Ron Paul has won no states,  119 delegates and 11 percent of the votes.