PARIS - French President Nicolas Sarkozy vowed on Sunday to tighten border controls, control immigration and fight crime as he launched his campaign for the presidential election runoff following a record first-round vote for the far right.

Sarkozy will face the first-round winner, Socialist Francois Hollande, in the second round on May 6. A near 20-percent score for the National Front's charismatic leader Marine Le Pen makes her a potential kingmaker and her supporters the biggest source of potential votes in the runoff. Le Pen refused on Sunday to endorse either the conservative incumbent or the challenger.