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(CNN) - John McCain clinched the Republican nomination tonight with big wins in Texas and Ohio.
But looking at the exit polls out of Texas - a state McCain must carry in the general election to win the presidency - trouble remains for the Arizona senator.
Despite the fact McCain is certain to carry his party's banner in the general election, he only narrowly carried Texas conservatives over Huckabee (48-40 percent). They made up more than two-thirds of all Texas Republican voters, and it is imperative they show up to vote for McCain in November. Also, McCain only managed to tie Huckabee among late deciders, another indication many Republicans aren't ready to rally behind McCain.
Another troubling statistic: More Texas Republican voters said they were looking for a candidate that shares their values over any other quality - and those voters picked Huckabee by 25 points over McCain (57-32 percent).
Translation: McCain captured his party's nomination tonight, but he still has a lot of work ahead of him to convince the base he's their guy.
Related: Watch McCain speak to supporters about being the Republican nominee
–CNN's Senior Political Analyst Bill Schneider