US voters tended to base choices on less-than-global issues. MOUNTAIN WEST.

The tapestry of power in the Rocky Mountain states has taken on both some new Democratic and Republican threads. Republicans made some important inroads Tuesday in the region's last remaining source of Democratic strength, governorships. This will help them when it comes time for House redistricting after the 1990 census.

But the Democrats won some key US Senate contests that helped them recapture the upper Chamber - despite the heavy campaigning of the enormously popular Republican President.

``In the Rocky Mountain area, it appears the move toward the Republican Party is either on hold or in reverse,'' says University of Utah political scientist Robert Benedict.

The win by Rep. Harry Reid over Jim Santini in the Nevada Senate race was a particularly big one for Democrats. It moved a GOP seat into the Democratic column and dealt a severe blow to any presidential aspirations of Paul Laxalt. The retiring Republican Senator had handpicked Santini as his successor.

In Colorado, the Democrats held onto the seat being vacated by Sen. Gary Hart with a narrow victory by Rep. Timothy Wirth over Rep. Ken Kramer. Both Wirth in Colorado and Reid in Nevada campaigned as pragmatic Democrats in nominally Republican areas.

The GOP hung onto retiring Sen. Barry Goldwater's seat in Arizona with a comfortable win by John McCain III, a former Vietnam prisoner of war. Incumbent Republican Don Nickles won re-election to the Senate in Oklahoma as well.

At the gubernatorial level, the GOP was hoping for a realignment in the Rocky Mountain states and the Southwest. They got a slight readjustment. Their biggest plum came in Texas, where former Gov. Clements won back his old job from Democrat Mark White.

A former governor also triumphed in Oklahoma. Henry Bellmon's victory put the governor's mansion into GOP hands. The biggest Republican surprise, though, came in Arizona, where auto dealer Evan Mecham bested Democrat Carolyn Warner and an independent candidate. New Mexico voters chose Republican kGarrey E. Carruthers to succeed Democrat Toney Anaya.

On the other hand, the GOP had hoped to break the Democrats' 12-year lock on the governorship in Wyoming. But Democrat Mike Sullivan upset GOP favorite Pete Simpson. The Democrats also held onto the statehouses in Nevada and Colorado.

There will be little change in US House delegations. They will remain largely in GOP hands in the Rocky Mountain West and Democratic hands in Texas. Overall upshot: no strong repudiation of Reagan administration policies. The races turned more on local issues and candidates.

-Scott Armstrong, Los Angeles