There are a lot of wide open spaces in the Rocky Mountain West — but few competitive races.  

Despite a dearth of important contests, the races to watch here could be good indicators of which party has the upper hand in the fall.  

Three races dropped from our Top 5 list since last summer . Idaho’s 2nd District is no longer worth watching after Rep. Mike Simpson defeated attorney Bryan Smith in the Republican primary. The Montana Senate race is now a likely GOP takeover after appointed Sen. John Walsh faced plagiarism charges and dropped out of the race. And Utah’s 4th District is all-but-over since Democratic Rep. Jim Matheson chose retirement over another competitive race with Republican Mia Love. Here are the top four races to watch in the Mountain region (since I couldn’t come up with five):  

Colorado Senate. GOP Rep. Cory Gardner’s late decision to challenge Democratic Sen. Mark Udall took this race from no-shot to a legitimate Republican takeover opportunity. After some initial volatility, the race appears to have stabilized into a highly competitive contest. President Barack Obama’s job rating could cast a shadow over this contest. The Rothenberg Political Report /Roll Call rating: Tossup/Tilts Democratic .  

Colorado’s 6th District. Republican Rep. Mike Coffman and Democratic former state Speaker Andrew Romanoff are locked in one of the most competitive House races anywhere in the country. Coffman starts the general election race in remarkably strong position, but Romanoff has more than enough money to close the gap. The Rothenberg Political Report /Roll Call rating: Pure Tossup .  

Colorado Governor. Former Rep. Bob Beauprez was a late entry into the GOP race for governor, but he isn’t as strong of a statewide candidate as Gardner. That doesn’t mean Beauprez can’t defeat Democratic Gov. John Hickenlooper. The incumbent’s numbers have fluctuated from very vulnerable to decent, and this has now settled into a competitive race. The Rothenberg Political Report /Roll Call rating: Leans Democratic .  

Montana’s At-Large District. Walsh was always a long-shot to win a full Senate term but his ultimate demise might have torpedoed Democrat John Lewis’s chances of taking over Rep. Steve Daines’ open House seat. Lewis, who just went up on television with a 30-second ad, faces Republican Ryan Zinke in November. The Rothenberg Political Report /Roll Call rating: Republican Favored .  

www.youtube.com/watch?v=Tl_HHZUjMKk  

What races would you add to or subtract from the list?  

Note: This is the sixth in a series of regional looks at the most competitive House and Senate races to watch. The Mountain Region includes Colorado, Idaho, Montana, Utah and Wyoming.

The previous regions: Mid-Atlantic, New England, Midwest, the Plains and West.