(CBS News) After months of campaigning, CBS News estimates that Mitt Romney on Tuesday will surpass the 1,144 delegates necessary to clinch the Republican presidential nomination.
CBS News has been tracking delegates throughout the primaries and caucuses, including interviews with Republican delegates across the country. The former Massachusetts governor has amassed more than a thousand delegates from these contests and CBS News has also confirmed that he has the support of 83 of the 123 delegates who are Republican National Committee members and are free to support who they choose.
He's in easy striking distance now and delegates from Texas, which finishes voting later tonight, are expected to put him over the top.
Texas primary results
CBS News estimated delegate count
Full primary campaign results
It has been a year since Romney formally announced his candidacy. Along the way he's won 30 states en route to the nomination. It was a long battle partially due to new Republican party rules, in which more states awarded delegates proportionally, making it more difficult for Romney -- or any candidate -- to wrap the nomination up early.
Romney sought the Republican nomination for president in 2008 but left the race in February, shortly after the Super Tuesday contests.
Texas Congressman Ron Paul, who continues to focus on winning delegates at state and district conventions, had 106 delegates heading into the Texas primary.
Former candidates Newt Gingrich and Rick Santorum also won a number of delegates during their presidential campaigns. While both have publicly endorsed Romney, they have yet to release their delegates, which means many of these delegates remain bound to Gingrich and Santorum -- at least for now.
Romney will officially be nominated at the Republican national convention in August in Tampa, Florida.