The Des Moines Register reports that the state constitutional amendment is winning 66%-34% with about 87% of the vote counted. The text will read,
The right of the people to keep and bear arms shall not be infringed. The sovereign state of Iowa affirms and recognizes this right to be a fundamental individual right. Any and all restrictions of this right shall be subject to strict scrutiny.
For lists of the current and past state constitutional provisions as of 2006 (a few have been added or changed since), both by state and by date, see here.