Gov. Janet Napolitano has decided to move up Arizona's presidential primary by three weeks to Feb. 5, joining at least 19 other states with primaries or caucuses on that date.

Napolitano will invoke her authority under state law and move the primary from Feb. 26, aides told The Associated Press on Tuesday.

The governor chose the new date because it provides the earliest chance for Arizona to have its primary without breaking national political party rules, said Noah Kroloff, deputy chief of staff for policy. Other states with primaries the same day include California, Illinois, New Jersey and New York.

Napolitano, a Democrat, believes Arizonans will benefit from having an early primary because candidates will be more likely to visit the state and learn about immigration, water and growth issues of concern in the state, Kroloff said.

"Sometimes they enter the presidential debates and sometimes they don't, but if you have Arizona in a position where we're early like this, the candidates are going to have to be in a position to think about them, and that's the advantage for Arizona," Kroloff said.

Several other states are trying to move their primaries or caucuses to dates earlier than permitted by party rules.